Text Categorization and Semantic Browsing withSelf-Organizing Maps on non-euclidean Spaces

Jorg Ontrup and Helge Ritter

Neuroinformatics GroupFaculty of TechnologyBielefeld University

D-33501 Bielefeld, Germany

Abstract This paper introduces a new type of Self-Organizing Map(SOM) for Text Categorization and Semantic Browsing. We propose a“hyperbolic SOM” (HSOM) based on a regular tesselation of the hy-perbolic plane, which is a non-euclidean space characterized by constantnegative gaussian curvature. This approach is motivated by the observa-tion that hyperbolic spaces possess a geometry where the size of a neigh-borhood around a point increases exponentially and therefore providesmore freedom to map a complex information space such as language intospatial relations. These theoretical findings are supported by our experi-ments, which show that hyperbolic SOMs can successfully be applied totext categorization and yield results comparable to other state-of-the-artmethods. Furthermore we demonstrate that the HSOM is able to maplarge text collections in a semantically meaningful way and thereforeallows a “semantic browsing” of text databases.

1 Introduction

For many tasks of exploraty data analysis the creation of Self-Organizing Maps(SOM) for data visualization, as introduced by Kohonen more than a decadeago, has become a widely used tool in many fields [7].

So far, the overwhelming majority of SOM approaches have taken it forgranted to use (some subregion of) a flat space as their data model and, moti-vated by its convenience for visualization, have favored the (suitably discretized)euclidean plane as their chief “canvas” for the generated mappings (for a few no-table exceptions using tree- or hypercubical lattices see e. g. [1, 8, 14]).

However, even if our thinking is deeply entrenched with euclidean space, anobvious limiting factor is the rather restricted neighborhood that “fits” arounda point on a euclidean 2d surface. Recently, it has been observed that a particu-lar type of non-euclidean spaces, the hyperbolic spaces that are characterized byuniform negative curvature, are very well suited to overcome this limitation [9]since their geometry is such that the size of a neighborhood around a point in-creases exponentially with its radius r (while in a D-dimensional euclidean spacethe growth follows the much slower power law rD). This exponential scalingbehavior fits very nicely with the scaling behavior within hierarchical, tree-like

Preprint submitted to PKDD-01 12th April 2001

structures, where the number of items r steps away from the root grows as br

where b is the (average) branching factor. This interesting property of hyperbolicspaces has been exploited for creating novel displays of large hierarchical struc-tures that are more accessible to visual inspection than in previous approaches[10].

Therefore, it appears very promising to use hyperbolic spaces also in con-junction with the SOM. The resulting hyperbolic SOMs (HSOMs) are basedon a tesselation of the hyperbolic plane (or some higher-dimensional hyperbolicspace) and their lattice neighborhood reflects the hyperbolic distance metric thatis responsible for the non-intuitive properties of hyperbolic spaces.

Since the notion of non-euclidean spaces may be unfamiliar to many readers,we first give a brief account of some basic properties of hyperbolic spaces that areexploited for hyperbolic SOMs. We then illustrate the properties of hyperbolicSOMs with computer experiments focusing on the field of text-mining.

2 Hyperbolic Spaces

Surfaces that possess negative gaussian curvature locally resemble the shape ofa “saddle”, i. e., the negative curvature shows up as a local bending into oppo-site normal directions, as we move on orthogonal lines along the surface. Thismay make it intuitively plausible that on such surfaces the area (and also thecircumference) of a circular neighborhood around a point can grow faster thanin the uncurved case. Requiring a constant negative curvature everywhere, leadsto a space known as the hyperbolic plane H2 (with analogous generalizations tohigher dimensions)[2, 20]. The geometry of H2 is a standard topic in Rieman-nian geometry (see, e. g. [19, 13]), and the relationships for the area A and thecircumference C of a circle of radius r are given by

A = 4π sinh2(r/2), C = 2π sinh(r) . (1)

These formulae exhibit the highly remarkable property that both quantities growexponentially with the radius r (whereas in the limit r → 0 the curvature becomesinsignificant and we recover the familiar laws for flat IR2). It is this property thatwas observed in [9] to make hyperbolic spaces extremely useful for accommodat-ing hierarchical structures: their neighborhoods are in a sense “much larger”than in the non-curved euclidean (or in the even “smaller” positively curved)spaces.

To use this potential for the SOM, we must solve two problems: (i) we mustfind suitable discretization lattices on H2 to which we can “attach” the SOMprototype vectors. (ii) after having constructed the SOM, we must somehowproject the (hyperbolic!) lattice into “flat space” in order to be able to inspectthe generated maps.

2.1 Projections of Hyperbolic Spaces

To construct an isometric (i. e., distance preserving) embedding of the hyperbolicplane into a “flat” space, we may use a Minkowski space [12]. In such a space,

the squared distance d2 between two points (x, y, u) and (x′, y′, u′) is given by

d2 = (x− x′)2 + (y − y′)2 − (u− u′)2 (2)

i. e., it ceases to be positive definite. Still, this is a space with zero curvatureand its somewhat peculiar distance measure allows to construct an isometricembedding of the hyperbolic plane H2, given by

x = sinh(ρ) cos(φ), y = sinh(ρ) sin(φ), u = cosh(ρ) , (3)

where (ρ, φ) are polar coordinates on the H2 (note the close analogy of (3)with the formulas for the embedding of a sphere by means of spherical polarcoordinates in IR3!). Under this embedding, the hyperbolic plane appears as thesurface M swept out by rotating the curve u2 = 1 + x2 + y2 about the u-axis1.

A

D

C

B

u

S

O 1

N

1

M

Figure 1: Construction steps underly-ing Klein and Poincare-models of thespace H2

From this embedding, we can constructtwo further ones, the so-called Klein modeland the Poincare model [2, 3, 6](the latterwill be used to visualize hyperbolic SOMsbelow). Both achieve a projection of theinfinite H2 into the unit disk, however, atthe price of distorting distances. The Kleinmodel is obtained by projecting the pointsof M onto the plane u = 1 along rays pass-ing through the origin O (see Fig. 1). Obvi-ously, this projects all points of M into the“flat” unit disk x2 + y2 < 1 of IR2. (e. g.,A 7→ B). The Poincare Model results if weadd two further steps: first a perpendicu-lar projection of the Klein Model (e. g., a

point B) onto the (“northern”) surface of the unit sphere centered at the origin(point C), and then a stereographic projection of the “northern” hemisphereonto the unit circle about the origin in the ground plane u = 0 (point D). Itturns out that the resulting projection of H2 has a number of pleasant proper-ties, among them the preservation of angles and the mapping of shortest pathsonto circular arcs belonging to circles that intersect the unit disk at right angles.Distances in the original H2 are strongly distorted in its Poincare (and also inthe Klein) image (cf. Eq. (5)), however, in a rather useful way: the mappingexhibits a strong “fisheye”-effect. The neighborhood of the H2 origin is mappedalmost faithfully (up to a linear shrinkage factor of 2), while more distant re-gions become increasingly “squeezed”. Since asymptotically the radial distancesand the circumference grow both according to the same exponential law, thesqueezing is “conformal”, i. e., (sufficiently small) shapes painted onto H2 arenot deformed, only their size shrinks with increasing distance from the origin.1 the alert reader may notice the absence of the previously described local saddle

structure; this is a consequence of the use of a Minkowski metric for the embeddingspace, which is not completely compatible with our “euclidean” expectations.

Figure 2: Regular triangle tesselations of the hyperbolic plane, projected into the unitdisk using the Poincare mapping. The leftmost tesselation shows the case where theminimal number (n = 7) of equilateral triangles meet at each vertex and is best suitedfor the hyperbolic SOM, since tesselations for larger values of n (right: n = 10) leadto bigger triangles. In the Poincare projection, only sides passing through the originappear straight, all other sides appear as circular arcs, although in the original spaceall triangles are congruent.

By translating the original H2 the fisheye-fovea can be moved to any other partof H2, allowing to selectively zoom-in on interesting portions of a map paintedon H2 while still keeping a coarser view of its surrounding context.

2.2 Tesselations of the Hyperbolic Plane

To complete the set-up for a hyperbolic SOM we still need an equivalent of aregular grid in the hyperbolic plane. We use the following results [3, 11]: whilethe choices for tesselations with congruent polygons on the sphere and even inthe plane are such that each grid point is surrounded by the same number nof neighbors are severely limited (the only possible values for n being 3,4,5 onthe sphere, and 3,4,6 in the plane), there is an infinite set of choices for thehyperbolic plane. In the following, we will restrict ourselves to lattices consist-ing of equilateral triangles only. In this case, there is for each n ≥ 7 a regulartesselation such that each vertex is surrounded by n congruent equilateral trian-gles. Fig. 2 shows two example tesselations (for the minimal value of n = 7 andfor n = 10), using the Poincare model for their visualization. While in Fig. 2these tesselations appear non-uniform, this is only due to the fisheye effect of thePoincare projection. In the original H2, each tesselation triangle has the samesize, and this can be checked by re-projecting any distant part of the tessela-tion into the center of the Poincare disk, after which it looks identical (up to apossible rotation) to the center of Fig. 2.

One way to generate these tesselations algorithmically is by repeated appli-cation of a suitable set of generators of their symmetry group to a (suitablysized, cf. below) “starting triangle”, for more details cf [15].

3 Hyperbolic SOM Algorithm

We have now all ingredients required for a “hyperbolic SOM”. In the following,we use the regular triangle tesselation with vertex order n = 7, which leads tothe “finest” tesselation that is possible (in H2, the angles of a triangle uniquelydetermine its size). Using the construction scheme sketched in the previous sec-tion, we can organize the nodes of such a lattice as “rings” around an originnode (i. e., it is simplest to build approximately “circular” lattices). The num-bers of nodes of such a lattice grows very rapidly (asymptotically exponentially)with the chosen lattice radius R (its number of rings). For instance, for n = 7,Table 1 shows the total number NR of nodes of the resulting regular hyperboliclattices with different radii ranging from R = 1 to R = 10. Each lattice node rcarries a prototype vector wr ∈ IRD from some D-dimensional feature space (ifwe wish to make any non-standard assumptions about the metric structure ofthis space, we would build this into the distance metric that is used for deter-mining the best-match node). The SOM is then formed in the usual way, e. g.,in on-line mode by repeatedly determining the winner node s and adjusting allnodes r ∈ N(s, t) in a radial lattice neighborhood N(s, t) around s according tothe familiar rule

∆wr = ηhrs(x−wr) (4)

with hrs = exp(−d2(r, s)/2σ2). However, since we now work on a hyperboliclattice, we have to determine both the neighborhood N(s, t) and the (squared)node distance d2(r, s) according to the natural metric that is inherited by thehyperbolic lattice.

Table 1: Node numbers NR of hyperbolic triangle lattices with vertex order 7 fordifferent numbers R of “node rings” around the origin.

R 1 2 3 4 5 6 7 8 9 10

NR 8 29 85 232 617 1625 4264 11173 29261 76616

The simplest way to do this is to keep with each node r a complex numberzr to identify its position in the Poincare model. The node distance is then given(using the Poincare model, see e. g. [19]) as

d = 2arctanh(∣∣∣∣ zr − zs

1− zs · zr

∣∣∣∣) . (5)

The neighborhood N(t, s) can be defined as the subset of nodes within acertain graph distance (which is chosen as a small multiple of the neighborhoodradius σ) around s.

Like the standard SOM, also the hyperbolic SOM can become trapped intopological defects. Therefore, it is also important here to control the neighbor-hood radius σ(t) from an initially large to a final small value (for details on thisand some further means to optimize convergence, see [15]).

4 Experiments

Some introductory experiments where several examples illustrate the favorableproperties of the HSOM as compared to the “standard” euclidean SOM can befound in [15].

4.1 Text Categorization

While - similar as for the SOM [7] - a very high classification accuracy is of a sec-ondary importance to visualization, a good classification performance is still im-portant to obtain useful maps of text categories. With the ever growing amountof available information on the Internet, automatic text categorization based onmachine learning techniques has become a key task where high-dimensional inputspaces with few irrelevant features are involved [4]. Here the goal is the assign-ment of natural language documents to a number of predefined categories (eachdocument dj can belong to one, several or none of the categories ci). Achievinga high classification accuracy is an important prerequisite for automating highvolume information organization and management tasks.

Text Representation. In order to apply the HSOM to natural text catego-rization, we follow the widely used vector-space-model of Information Retrieval(IR). We applied a word stemming algorithm2 such that for example the words“retrieved”, “retrieval” and “retrieve” are mapped to the term “retrief”. Thevalue of fi of the feature vector f(di) for document dj is then determined by thefrequency of which term ti occurs in that document. Following standard prac-tice [16] we choose a term frequency × inverse document frequency weightingscheme:

fi = tf(ti, j) log(

N

df(ti)

), (6)

where the term frequency tf(ti, j) denotes the number of times term ti occursin dj , N the number of documents in the training set and df(ti) the documentfrequency of ti, i. e. the number of documents ti occurs in. Additionally, we builta stop list of the most and least frequent terms specific to the training set andomitted those from the feature vectors, since they have no descriptive functionwith respect to that text corpus.

HSOM Text Categorization. The HSOM can be utilised for text categoriza-tion in the following manner (Fig. 3). In a first step, the training set is usedto adapt the weight vectors wr according to (4). During the second step, the

2 We applied the triestem function of the SMART system by G. Salton and C. Buckley(ftp://ftp.cs.cornell.edu/pub/smart/).

C1C6

associated labels

finding best match

documentunknown

C1C6

associated labels

finding best match

documentunknown

...C8C4

C6C1

Training set withknown categories

...C8C4

C6C1

Training set withknown categories

(b) Step 2: Labelling

(a) Step 1: Training

C1C6

Trainingcollection

Adaptionof reference

vectors

(c) Step 3: Classification

Figure 3: Text categorization with the HSOM: First the training set is used to build aninternal model of the collection represented by the HSOM’s reference vectors. In (b) foreach training document the winner nodes are labelled with the document’s category.These labels are used in the classification step (c) where an unknown document is“thrown” onto the map and labelled with the categories of its corresponding bestmatch node.

training set is mapped onto the HSOM lattice. To this end, for each trainingexample dj its best match node s is determined such that

|f(dj)−ws| 6 |f(dj)−wr| ∀r , (7)

where f(dj) denotes the feature vector of document dj , as described above. Afterall examples have been presented to the net, each node is labelled with the unionUr of all categories that belonged to the documents that were mapped to thisnode. A new, unknown text is then classified into the union Us of categories whichare associated with its winner node s selected in the HSOM. In order to evaluatethe HSOM’s categorization performance, we furthermore use cos(ws,f(dj)) asa confidence measure for the classification result.

Text Collection. The text collection consists of movie reviews taken from therec.art.movies.reviews newsgroup. Genre information from the Internet MovieDatabase (http://www.imdb.com) was used to build a joined database contain-ing the review texts plus the genres from their corresponding movies as the cat-egories. To build the training text collection, for each of the most prominent 17categories 20 movies were randomly selected. For each of these movies, 3 reviewtexts were chosen by chance. Therefore, the training collection contained 1020distinct documents. The test text collection was constructed in the same manner

with the restriction that it must not contain any document of the training set.After word stemming and stop word removal we arrived at approximately 5000distinct terms for the construction of the feature vectors.

Performance Evaluation. The classification effectiveness is commonly mea-sured in terms of precision P and recall R [17], which can be estimated as

Pi =TPi

TPi + FPi, Ri =

TPiTPi + FNi

, (8)

where TPi and TNi are the numbers of documents correctly classified, and cor-rectly not classified to ci, respectively. Analogous, FPi and FNi are the numbersof documents wrongly classified and not classified to ci, respectively. By adjust-ing a threshold which is compared with the confidence value cos(ws,f(dj)) ofthe classifier, the number of retrieved documents can be controlled. In order toobtain an overall performance measure for all categories, we applied the microav-eraging method [21]. Furthermore, the breakeven point of precision and recall,i. e. the value at which P = R is a frequently given single number to measurethe effectiveness determined by both values P and R [17].

In order to assess the HSOM’s performance for text categorization, we haveused a k-nearest neighbour (k-NN) classifier which was found to show very goodresults on text categorization tasks [21]. Apart from boosting methods [18] onlysupport vector machines [5] have shown better performances. The confidencelevel of a k-NN classifier to assign document dj to class ci is

Ck-NNi (dj) =

∑dz∈TRk(dj)

aiz · cos(dj , dz) , (9)

where TRk(dj) is the set of k documents dz for which cos(dj , dz) is maximum.The assignment factor aiz is 1, if dz belongs to category ci and 0 otherwise.According to [21, 5] we have chosen the k = 30 nearest neighbours.

Text Categorization Results. Precision-recall-diagrams for three categoriesand the microaveraged diagrams for all categories are shown in Fig. 4. The singlecategory and microaveraged break-even points are layed out in Table 2.

It is notable that the HSOM performs significantly worse if only a few doc-uments are recalled, but the precision in cases of high recall values is very closeto that of the k-NN classifier. Since one is usually interested in high precisionin conjunction with high recall, the suboptimal results for low recall values donot really affect the usefulness of the HSOM for the purpose of text categoriza-tion3. Thus, our results indicate that the HSOM does not perform better thana k-NN classifier, but it does not play significantly worse either. Since the main3 We also believe that a more clever heuristic than the simple distance to the bestmatch

node in order to determine the evidence value of a classification will further improveaccuracy for low retrieval rates.

purpose of the HSOM is the visualization of relationships between texts andtext categories, we believe that the observed categorization performance of theHSOM compares sufficiently well with the more specialized (non-visualization)approaches to warrant its efficient use for creating insightful maps of large bodiesof document data.

0.4

0.6

0.7

0.8

0.9

1

0 0.2 0.4 0.6 0.8 1

Romance

Thriller

Drama

(a) k-NN

0.4

0.6

0.7

0.8

0.9

1

0 0.2 0.4 0.6 0.8 1

Romance

Thriller

Drama

(b) HSOM

0.4

0.6

0.7

0.8

0.9

1

0 0.2 0.4 0.6 0.8 1

k-NN classifier

HSOM

(c) Microaveraged

Figure 4: Precision-recall-diagrams for the three categories Drama, Thriller and Ro-mance. (a) shows the results for the k-NN classifier, (b) for the HSOM. In (c) themicroaveraged diagrams for both methods are shown.

Table 2: Precision-recall breakeven points for the most prominent categories. In mostcases the k-NN performs better than the HSOM, but for the categories “Animation”,“Fantasy” and “Musical” the HSOM yields better results.

Action Advent. Animation Comedy Crime Docum. Drama

HSOM 81.6 75.4 86.9 81.3 84.5 86.7 82.5

k-NN 87.3 83.0 84.5 87.6 90.5 98.0 85.8

Fantasy Horror Musical Mystery Romance Sci-Fi Thriller µ-avg.

HSOM 81.6 78.6 82.5 84.6 82.8 76.2 86.8 81.1

k-NN 75.0 88.9 81.2 86.1 87.8 89.3 89.1 86.4

4.2 Semantic Browsing

A major advantage of the HSOM is its remarkable capability to map high-dimensional similarity relationships to a low-dimensional space which can bemore easily handled and interpreted by the human observer. This feature andthe particular “fisheye” capability motivates our approach to visualize wholetext collections with the HSOM. With just as little as 5 rings (c.f. Table 1), wecan handle well over 500 prototype vectors which are able to represent differenttypes of texts. The nodes are labelled with those document titles which resembletheir prototype vectors most closely. We additionally map symbols to the nodeswhich correspond to the categories associated with the prototypes. We can nowinteractively change the visual focus to those regions which show an interestingstructure. In Fig. 5(a) for example we have “zoomed” into a region of the map

which indicated a cluster of “Animation” films. As a closer inspection shows,this region of the map resembles movie reviews all connected to Disney’s typicalanimations released during Christmas time. In Fig. 5(b) the focal view wasmoved to a region connected to “Action” and “Fantasy” films. It does not onlyshow the movies of the “Batman” series in a limited area of the map, but alsoa “Zorro” movie in the neigborhood - which makes a lot of sense, as the maincharacters of the films indeed have a semantic relation.

Blues Brothers 2000 (1998)Blues Brothers 2000 (1998)Babe (1995)Dark City (1998)Crow, The (1994)Vampires (1998)Vampires (1998)Donnie Brasco (1997)Devil’s Advocate, The (1997)Casino (1995)Casino (1995)Looking for Richard (1996)Richard III (1995)L.A. Confidential (1997)Spawn (1997/I)Edge, The (1997/I)Edge, The (1997/I)Primary Colors (1998)Primary Colors (1998)Full Metal Jacket (1987)Full Metal Jacket (1987)Boot, Das (1981)Last of the Mohicans, The (1992)Geronimo: An American Legend (1993)Geronimo: An American Legend (1993)Wyatt Earp (1994)Quick and the Dead, The (1995)Lost Highway (1997)Welcome To Sarajevo (1997)Sphere (1998)Wag the Dog (1997)Strange Days (1995)Sphere (1998)Frighteners, The (1996)Frighteners, The (1996)X Files, The (1998)Species II (1998)Bulworth (1998)Mimic (1997)Gattaca (1997)Simple Plan, A (1998)Se7en (1995)Everest (1998)Clay Pigeons (1998)MisØrables, Les (1998)Full Monty, The (1997)Pulp Fiction (1994)Jackie Brown (1997)Event Horizon (1997)Event Horizon (1997)When We Were Kings (1996)When We Were Kings (1996)Jumanji (1995)Jumanji (1995)Mortal Kombat: Annihilation (1997)Playing God (1997)Contact (1997/I)English Patient, The (1996)Amistad (1997)Backbeat (1993)Spanish Prisoner, The (1997)Six Days Seven Nights (1998)Selena (1997)Paradise Lost: The Child Murders at Robin Hood Hills (1996)What Dreams May Come (1998)As Good As It Gets (1997)Jerry Maguire (1996)My Best Friend’s Wedding (1997)Wedding Singer, The (1998)Kiss the Girls (1997)Avengers, The (1998)Anaconda (1997)Dead Man (1995)Natural Born Killers (1994)Last Man Standing (1996/I)Last Man Standing (1996/I)Unforgiven (1992)Midnight in the Garden of Good and Evil (1997)Wild Bill (1995)Wild Bill (1995)Wild Bill (1995)Wild Bunch, The (1969)Anastasia (1997)

Enemy of the State (1998)Men in Black (1997)

Small Soldiers (1998)Muppet Treasure Island (1996)

Mulan (1998)

Little Mermaid, The (1989)

Quest for Camelot (1998)

Little Mermaid, The (1989)

Hunchback of Notre Dame, The (1996)

Hercules (1997/I)

Lion King, The (1994)

Hunchback of Notre Dame, The (1996)

Man in the Iron Mask, The (1998/I)

Mask, The (1994)Out of Sight (1998)Perfect Murder, A (1998)Scream (1996)Scream 2 (1997)Scream (1996)

Titanic (1997)Richard III (1995)Walk in the Clouds, A (1995)

True Lies (1994)Rob Roy (1995)Rob Roy (1995)Cop Land (1997)James and the Giant Peach (1996)Starship Troopers (1997)Starship Troopers (1997)Batman & Robin (1997)Batman & Robin (1997)Batman Forever (1995)Batman Returns (1992)Batman (1989)Batman Forever (1995)Batman & Robin (1997)Star Trek: Insurrection (1998)Star Trek: Insurrection (1998)Star Trek: First Contact (1996)Star Trek: First Contact (1996)Fifth Element, The (1997)Rush Hour (1998)Lost in Space (1998)Schindler’s List (1993)Star Wars (1977)Star Wars (1977)Deep Impact (1998)Deep Impact (1998)Horse Whisperer, The (1998)Armageddon (1998)Armageddon (1998)Godzilla (1998)Godzilla (1998)Lost World: Jurassic Park, The (1997)Lost World: Jurassic Park, The (1997)Jurassic Park (1993)Lost World: Jurassic Park, The (1997)Casper (1995)Casper (1995)Independence Day (1996)Independence Day (1996)Big One, The (1997)Roger & Me (1989)Big One, The (1997)Evita (1996)Wild Man Blues (1998)Everyone Says I Love You (1996)Antz (1998)Bug’s Life, A (1998)Microcosmos: Le peuple de l’herbe (1996)Full Tilt Boogie (1997)Full Tilt Boogie (1997)Boogie Nights (1997)Boogie Nights (1997)Boogie Nights (1997)Crumb (1994)Newton Boys, The (1998)Grease (1978)Crumb (1994)Psycho (1998)Good Will Hunting (1997)Good Will Hunting (1997)Rounders (1998)Rounders (1998)Ballad of Little Jo, The (1993)Little Women (1994)Little Women (1994)Truman Show, The (1998)Cool World (1992)Cool World (1992)Cool World (1992)Usual Suspects, The (1995)Fear and Loathing in Las Vegas (1998)Fear and Loathing in Las Vegas (1998)Wyatt Earp (1994)Waterworld (1995)Waterworld (1995)Wild Things (1998)Wild Things (1998)Postman, The (1997)Postman, The (1997)Mars Attacks! (1996)Independence Day (1996)Game, The (1997)Pulp Fiction (1994)Vertigo (1958)Buono, il brutto, il cattivo, Il (1966)Lone Star (1996)My Best Friend’s Wedding (1997)Buono, il brutto, il cattivo, Il (1966)Blazing Saddles (1974)Dracula (1992)Dracula (1992)Meet Joe Black (1998)Meet Joe Black (1998)Mighty Joe Young (1998)You’ve Got Mail (1998)Celluloid Closet, The (1995)You’ve Got Mail (1998)Big Lebowski, The (1998)Blues Brothers 2000 (1998)Babe: Pig in the City (1998)Blade (1998)In Love and War (1996)Thin Red Line, The (1998)Hearts of Darkness: A Filmmaker’s Apocalypse (1991)Dances with Wolves (1990)There’s Something About Mary (1998)Strange Days (1995)Alien: Resurrection (1997)Fallen (1998)Heat (1995)English Patient, The (1996)Backbeat (1993)

Anaconda (1997)

Buono, il brutto, il cattivo, Il (1966)

Mars Attacks! (1996)Toy Story (1995)

Beauty and the Beast: The Enchanted Christmas (1997) (V)

Pocahontas (1995)

Lion King, The (1994)

Pocahontas (1995)I Know What You Did Last Summer (1997)Halloween H20: Twenty Years Later (1998)

Nightmare Before Christmas, The (1993)

Evita (1996)Antz (1998)Full Tilt Boogie (1997)Newton Boys, The (1998)Heaven & Earth (1993)Aladdin (1992)Conspiracy Theory (1997)Meet Joe Black (1998)Doctor Dolittle (1998)Tomorrow Never Dies (1997)Courage Under Fire (1996)Quest for Camelot (1998)Nothing to Lose (1997)Alien: Resurrection (1997)Urban Legend (1998)Con Air (1997)Red Corner (1997)

Seven Years in Tibet (1997)Secret of Roan Inish, The (1994)

Pleasantville (1998)Fast, Cheap & Out of Control (1997)

Mars Attacks! (1996)

Beauty and the Beast (1991)

Beauty and the Beast (1991)

I Know What You Did Last Summer (1997)Faculty, The (1998)Desperado (1995)

James and the Giant Peach (1996)

Mask of Zorro, The (1998)

Bad Girls (1994/I)Unzipped (1995)City of Angels (1998)Prince of Egypt, The (1998)Anne Frank Remembered (1995)Hoop Dreams (1994)City Slickers II: The Legend of Curly’s Gold (1994)Maverick (1994)Braveheart (1995)Heaven & Earth (1993)Back to the Future Part III (1990)Rugrats Movie, The (1998)Parent Trap, The (1998)Tomorrow Never Dies (1997)Matilda (1996)Air Force One (1997)Face/Off (1997)

Conspiracy Theory (1997)

Legends of the Fall (1994)Vertigo (1958)

Pocahontas (1995)

Desperado (1995)

Mask of Zorro, The (1998)Deep Rising (1998)Cruise, The (1998)Akira (1988)Prince of Egypt, The (1998)Crumb (1994)4 Little Girls (1997)Krippendorf’s Tribe (1998)Beavis and Butt-head Do America (1996)Kiss the Girls (1997)

Clay Pigeons (1998)Secret of Roan Inish, The (1994)

Casper (1995)Anaconda (1997)Batman Forever (1995)Avengers, The (1998)Fifth Element, The (1997)

Blues Brothers 2000 (1998)Blues Brothers 2000 (1998)Babe (1995)Dark City (1998)Crow, The (1994)Vampires (1998)Vampires (1998)Donnie Brasco (1997)Devil’s Advocate, The (1997)Casino (1995)Casino (1995)Looking for Richard (1996)Richard III (1995)L.A. Confidential (1997)Spawn (1997/I)Edge, The (1997/I)Edge, The (1997/I)Primary Colors (1998)Primary Colors (1998)Full Metal Jacket (1987)Full Metal Jacket (1987)Boot, Das (1981)Last of the Mohicans, The (1992)Geronimo: An American Legend (1993)Geronimo: An American Legend (1993)Wyatt Earp (1994)Quick and the Dead, The (1995)Lost Highway (1997)Welcome To Sarajevo (1997)Sphere (1998)Wag the Dog (1997)Strange Days (1995)Sphere (1998)Frighteners, The (1996)Frighteners, The (1996)X Files, The (1998)Species II (1998)Bulworth (1998)Mimic (1997)Gattaca (1997)Simple Plan, A (1998)Se7en (1995)Everest (1998)Clay Pigeons (1998)MisØrables, Les (1998)Full Monty, The (1997)Pulp Fiction (1994)Jackie Brown (1997)Event Horizon (1997)Event Horizon (1997)When We Were Kings (1996)When We Were Kings (1996)Jumanji (1995)Jumanji (1995)Mortal Kombat: Annihilation (1997)Playing God (1997)Contact (1997/I)English Patient, The (1996)Amistad (1997)Backbeat (1993)Spanish Prisoner, The (1997)Six Days Seven Nights (1998)Selena (1997)Paradise Lost: The Child Murders at Robin Hood Hills (1996)What Dreams May Come (1998)As Good As It Gets (1997)Jerry Maguire (1996)My Best Friend’s Wedding (1997)Wedding Singer, The (1998)Kiss the Girls (1997)Avengers, The (1998)Anaconda (1997)Dead Man (1995)Natural Born Killers (1994)Last Man Standing (1996/I)Last Man Standing (1996/I)Unforgiven (1992)Midnight in the Garden of Good and Evil (1997)Wild Bill (1995)Wild Bill (1995)Wild Bill (1995)Wild Bunch, The (1969)Anastasia (1997)Enemy of the State (1998)Men in Black (1997)Small Soldiers (1998)Muppet Treasure Island (1996)Mulan (1998)Little Mermaid, The (1989)Quest for Camelot (1998)Little Mermaid, The (1989)Hunchback of Notre Dame, The (1996)Hercules (1997/I)Lion King, The (1994)Hunchback of Notre Dame, The (1996)Man in the Iron Mask, The (1998/I)Mask, The (1994)Out of Sight (1998)Perfect Murder, A (1998)Scream (1996)Scream 2 (1997)Scream (1996)Titanic (1997)Richard III (1995)Walk in the Clouds, A (1995)True Lies (1994)Rob Roy (1995)Rob Roy (1995)Cop Land (1997)James and the Giant Peach (1996)Starship Troopers (1997)Starship Troopers (1997)

Batman & Robin (1997)Batman & Robin (1997)

Batman Forever (1995)

Batman Returns (1992)

Batman (1989)

Batman Forever (1995)

Batman & Robin (1997)

Star Trek: Insurrection (1998)Star Trek: Insurrection (1998)

Star Trek: First Contact (1996)Star Trek: First Contact (1996)

Fifth Element, The (1997)

Rush Hour (1998)

Lost in Space (1998)

Schindler’s List (1993)

Star Wars (1977)Star Wars (1977)

Deep Impact (1998)Deep Impact (1998)Horse Whisperer, The (1998)Armageddon (1998)Armageddon (1998)

Godzilla (1998)Godzilla (1998)Lost World: Jurassic Park, The (1997)Lost World: Jurassic Park, The (1997)Jurassic Park (1993)Lost World: Jurassic Park, The (1997)Casper (1995)Casper (1995)Independence Day (1996)Independence Day (1996)Big One, The (1997)Roger & Me (1989)Big One, The (1997)Evita (1996)Wild Man Blues (1998)Everyone Says I Love You (1996)Antz (1998)Bug’s Life, A (1998)Microcosmos: Le peuple de l’herbe (1996)Full Tilt Boogie (1997)Full Tilt Boogie (1997)Boogie Nights (1997)Boogie Nights (1997)Boogie Nights (1997)Crumb (1994)Newton Boys, The (1998)Grease (1978)Crumb (1994)Psycho (1998)Good Will Hunting (1997)Good Will Hunting (1997)Rounders (1998)Rounders (1998)Ballad of Little Jo, The (1993)Little Women (1994)Little Women (1994)Truman Show, The (1998)Cool World (1992)Cool World (1992)Cool World (1992)Usual Suspects, The (1995)Fear and Loathing in Las Vegas (1998)Fear and Loathing in Las Vegas (1998)Wyatt Earp (1994)Waterworld (1995)Waterworld (1995)Wild Things (1998)Wild Things (1998)Postman, The (1997)Postman, The (1997)Mars Attacks! (1996)Independence Day (1996)Game, The (1997)Pulp Fiction (1994)Vertigo (1958)Buono, il brutto, il cattivo, Il (1966)Lone Star (1996)My Best Friend’s Wedding (1997)Buono, il brutto, il cattivo, Il (1966)Blazing Saddles (1974)Dracula (1992)Dracula (1992)Meet Joe Black (1998)Meet Joe Black (1998)Mighty Joe Young (1998)You’ve Got Mail (1998)Celluloid Closet, The (1995)You’ve Got Mail (1998)Big Lebowski, The (1998)Blues Brothers 2000 (1998)Babe: Pig in the City (1998)Blade (1998)In Love and War (1996)Thin Red Line, The (1998)Hearts of Darkness: A Filmmaker’s Apocalypse (1991)Dances with Wolves (1990)There’s Something About Mary (1998)Strange Days (1995)Alien: Resurrection (1997)Fallen (1998)Heat (1995)English Patient, The (1996)Backbeat (1993)Anaconda (1997)Buono, il brutto, il cattivo, Il (1966)Mars Attacks! (1996)Toy Story (1995)Beauty and the Beast: The Enchanted Christmas (1997) (V)Pocahontas (1995)Lion King, The (1994)Pocahontas (1995)I Know What You Did Last Summer (1997)Halloween H20: Twenty Years Later (1998)

Nightmare Before Christmas, The (1993)

Evita (1996)Antz (1998)Full Tilt Boogie (1997)Newton Boys, The (1998)Heaven & Earth (1993)Aladdin (1992)Conspiracy Theory (1997)Meet Joe Black (1998)Doctor Dolittle (1998)Tomorrow Never Dies (1997)Courage Under Fire (1996)Quest for Camelot (1998)Nothing to Lose (1997)Alien: Resurrection (1997)Urban Legend (1998)Con Air (1997)Red Corner (1997)Seven Years in Tibet (1997)Secret of Roan Inish, The (1994)Pleasantville (1998)Fast, Cheap & Out of Control (1997)Mars Attacks! (1996)Beauty and the Beast (1991)Beauty and the Beast (1991)I Know What You Did Last Summer (1997)Faculty, The (1998)Desperado (1995)

James and the Giant Peach (1996)

Mask of Zorro, The (1998) Bad Girls (1994/I)

Unzipped (1995)

City of Angels (1998)Prince of Egypt, The (1998)Anne Frank Remembered (1995)Hoop Dreams (1994)City Slickers II: The Legend of Curly’s Gold (1994)Maverick (1994)Braveheart (1995)Heaven & Earth (1993)Back to the Future Part III (1990)Rugrats Movie, The (1998)Parent Trap, The (1998)Tomorrow Never Dies (1997)Matilda (1996)Air Force One (1997)Face/Off (1997)Conspiracy Theory (1997)Legends of the Fall (1994)Vertigo (1958)Pocahontas (1995)

Desperado (1995)

Mask of Zorro, The (1998)

Deep Rising (1998)

Cruise, The (1998)

Akira (1988)Prince of Egypt, The (1998)Crumb (1994)

4 Little Girls (1997)Krippendorf’s Tribe (1998)Beavis and Butt-head Do America (1996)Kiss the Girls (1997)Clay Pigeons (1998)Secret of Roan Inish, The (1994)Casper (1995)

Anaconda (1997)

Batman Forever (1995)Avengers, The (1998)Fifth Element, The (1997)

Figure 5: By moving the visual focus of the HSOM, a large text collection can bebrowsed quite elegantly. In this example, the movie titles of their corresponding reviewtexts (there might be several reviews for one movie) are mapped. In (a) reviews ofDisney’s animations have been moved into the centre, (b) shows a region of the mapcontaining the “Batman” movies. Note, that the HSOM also mirrors the semanticalconnection between “Zorro” and “Batman”.

Love’s Labour’s Lost (2000)Love’s Labour’s Lost (2000)Love’s Labour’s Lost (2000)Love’s Labour’s Lost (2000)Love’s Labour’s Lost (2000)Love’s Labour’s Lost (2000)10 Things I Hate About You (1999)10 Things I Hate About You (1999)Shakespeare in Love (1998)Shakespeare in Love (1998)Shakespeare in Love (1998)Shakespeare in Love (1998)Looking for Richard (1996)Looking for Richard (1996)Wild Things (1998)Wild Things (1998)Wild Things (1998)Wild Things (1998)Michael (1996)Michael (1996)Michael (1996)Filth and the Fury, The (2000)Backbeat (1993)Backbeat (1993)Backbeat (1993)Backbeat (1993)Rob Roy (1995)Rob Roy (1995)Rob Roy (1995)Rob Roy (1995)Rob Roy (1995)Rob Roy (1995)Rob Roy (1995)Rob Roy (1995)Wag the Dog (1997)Wag the Dog (1997)Wag the Dog (1997)Mummy, The (1999)Mummy, The (1999)Mummy, The (1999)Mummy, The (1999)Anaconda (1997)Anaconda (1997)Anaconda (1997)Anaconda (1997)Prince of Egypt, The (1998)Prince of Egypt, The (1998)Prince of Egypt, The (1998)Starship Troopers (1997)Starship Troopers (1997)Starship Troopers (1997)Starship Troopers (1997)Starship Troopers (1997)Starship Troopers (1997)Big Lebowski, The (1998)Big Lebowski, The (1998)Big Lebowski, The (1998)Big Lebowski, The (1998)O Brother, Where Art Thou? (2000)O Brother, Where Art Thou? (2000)O Brother, Where Art Thou? (2000)O Brother, Where Art Thou? (2000)O Brother, Where Art Thou? (2000)O Brother, Where Art Thou? (2000)O Brother, Where Art Thou? (2000)O Brother, Where Art Thou? (2000)Fargo (1996)Fargo (1996)Fargo (1996)Wild Wild West (1999)Wild Wild West (1999)Wild Wild West (1999)Wild Wild West (1999)Men in Black (1997)Men in Black (1997)Men in Black (1997)Enemy of the State (1998)Enemy of the State (1998)Enemy of the State (1998)Enemy of the State (1998)Jerry Maguire (1996)Jerry Maguire (1996)Jerry Maguire (1996)Bug’s Life, A (1998)Bug’s Life, A (1998)Antz (1998)Antz (1998)Microcosmos: Le peuple de l’herbe (1996)Microcosmos: Le peuple de l’herbe (1996)Horse Whisperer, The (1998)Horse Whisperer, The (1998)Original Kings of Comedy, The (2000)Original Kings of Comedy, The (2000)Original Kings of Comedy, The (2000)Original Kings of Comedy, The (2000)Original Kings of Comedy, The (2000)Original Kings of Comedy, The (2000)Wild Man Blues (1998)Wild Man Blues (1998)Wild Man Blues (1998)Small Time Crooks (2000)Small Time Crooks (2000)Small Time Crooks (2000)MisØrables, Les (1998)MisØrables, Les (1998)MisØrables, Les (1998)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Iron Giant, The (1999)Iron Giant, The (1999)Iron Giant, The (1999)Iron Giant, The (1999)Instinct (1999)Instinct (1999)Congo (1995)Congo (1995)Congo (1995)Congo (1995)Congo (1995)Congo (1995)Congo (1995)Congo (1995)Spice World (1997)Spice World (1997)Green Mile, The (1999)Green Mile, The (1999)Snake Eyes (1998)Snake Eyes (1998)Snake Eyes (1998)Snake Eyes (1998)Snake Eyes (1998)Snake Eyes (1998)Bone Collector, The (1999)Bone Collector, The (1999)Bone Collector, The (1999)Fallen (1998)Fallen (1998)Fallen (1998)Fallen (1998)Fallen (1998)Fallen (1998)Corruptor, The (1999)Corruptor, The (1999)Corruptor, The (1999)Corruptor, The (1999)Replacement Killers, The (1998)Replacement Killers, The (1998)Face/Off (1997)Face/Off (1997)Face/Off (1997)Mission: Impossible (1996)Mission: Impossible (1996)Mission: Impossible (1996)Mission: Impossible (1996)Mission: Impossible (1996)Mission: Impossible (1996)James and the Giant Peach (1996)James and the Giant Peach (1996)James and the Giant Peach (1996)Nightmare Before Christmas, The (1993)Nightmare Before Christmas, The (1993)Nightmare Before Christmas, The (1993)Nightmare Before Christmas, The (1993)Nightmare Before Christmas, The (1993)Sleepy Hollow (1999)Sleepy Hollow (1999)Sleepy Hollow (1999)Sleepy Hollow (1999)Sleepy Hollow (1999)Sleepy Hollow (1999)Scream 2 (1997)Scream 2 (1997)Scream 2 (1997)Scream 3 (2000)Scream 3 (2000)Scream 3 (2000)Scream 3 (2000)Scream 3 (2000)Scream 3 (2000)Scream 3 (2000)Shanghai Noon (2000)Shanghai Noon (2000)Shanghai Noon (2000)Rush Hour (1998)Rush Hour (1998)Rush Hour (1998)Rounders (1998)Rounders (1998)Dead Man (1995)Dead Man (1995)Forrest Gump (1994)Forrest Gump (1994)Forrest Gump (1994)Quick and the Dead, The (1995)Quick and the Dead, The (1995)Quick and the Dead, The (1995)Quick and the Dead, The (1995)Quick and the Dead, The (1995)Quick and the Dead, The (1995)American Psycho (2000)American Psycho (2000)American Psycho (2000)American Psycho (2000)American Psycho (2000)American Psycho (2000)American Psycho (2000)American Psycho (2000)American Psycho (2000)Dances with Wolves (1990)Dances with Wolves (1990)Dances with Wolves (1990)Waterworld (1995)Waterworld (1995)Waterworld (1995)Waterworld (1995)Postman, The (1997)Postman, The (1997)Postman, The (1997)Postman, The (1997)Message in a Bottle (1999)Big One, The (1997)Big One, The (1997)Mr. Death: The Rise and Fall of Fred A. Leuchter, Jr. (1999)Mr. Death: The Rise and Fall of Fred A. Leuchter, Jr. (1999)Austin Powers: The Spy Who Shagged Me (1999)Sliding Doors (1998)Sliding Doors (1998)Sliding Doors (1998)Sliding Doors (1998)Perfect Murder, A (1998)Watcher, The (2000)Watcher, The (2000)Watcher, The (2000)Watcher, The (2000)Se7en (1995)Se7en (1995)Se7en (1995)Se7en (1995)eXistenZ (1999)Crash (1996)Crash (1996)Breakdown (1997)Breakdown (1997)Breakdown (1997)Breakdown (1997)Runaway Bride (1999)Runaway Bride (1999)My Best Friend’s Wedding (1997)My Best Friend’s Wedding (1997)Little Nicky (2000)Little Nicky (2000)Little Nicky (2000)Wedding Singer, The (1998)Wedding Singer, The (1998)Wedding Singer, The (1998)Wedding Singer, The (1998)Wedding Singer, The (1998)Wedding Singer, The (1998)Apocalypse Now (1979)Apocalypse Now (1979)Apocalypse Now (1979)Preacher’s Wife, The (1996)Preacher’s Wife, The (1996)Preacher’s Wife, The (1996)Anne Frank Remembered (1995)Anne Frank Remembered (1995)Selena (1997)Selena (1997)Selena (1997)Selena (1997)Cop Land (1997)Cop Land (1997)Bulworth (1998)Bulworth (1998)Bulworth (1998)Boot, Das (1981)Boot, Das (1981)Boot, Das (1981)U-571 (2000)U-571 (2000)U-571 (2000)U-571 (2000)Boot, Das (1981)Boot, Das (1981)Boot, Das (1981)Hoop Dreams (1994)Mediterraneo (1991)Mediterraneo (1991)Crumb (1994)Fast, Cheap & Out of Control (1997)Edge, The (1997)Edge, The (1997)Edge, The (1997)Edge, The (1997)Dancer in the Dark (2000)Dancer in the Dark (2000)Dancer in the Dark (2000)Dancer in the Dark (2000)Keeping the Faith (2000)Keeping the Faith (2000)Keeping the Faith (2000)Tango (1998)Tango (1998)Maverick (1994)Maverick (1994)Maverick (1994)Maverick (1994)Out of Sight (1998)Out of Sight (1998)Out of Sight (1998)Out of Sight (1998)Out of Sight (1998)Out of Sight (1998)Out of Sight (1998)Out of Sight (1998)L.A. Confidential (1997)L.A. Confidential (1997)L.A. Confidential (1997)L.A. Confidential (1997)Good Will Hunting (1997)Sixth Sense, The (1999)Sixth Sense, The (1999)Sixth Sense, The (1999)Unbreakable (2000)Unbreakable (2000)Unbreakable (2000)Unbreakable (2000)Unbreakable (2000)Unbreakable (2000)Soldier (1998)Soldier (1998)Soldier (1998)Soldier (1998)Haunting, The (1999)Haunting, The (1999)Haunting, The (1999)Haunting, The (1999)Haunting, The (1999)Haunting, The (1999)Six Days Seven Nights (1998)Six Days Seven Nights (1998)Six Days Seven Nights (1998)Six Days Seven Nights (1998)Lake Placid (1999)Lake Placid (1999)20 Dates (1998)20 Dates (1998)20 Dates (1998)Eyes Wide Shut (1999)Eyes Wide Shut (1999)Eyes Wide Shut (1999)Eyes Wide Shut (1999)Peacemaker, The (1997)Peacemaker, The (1997)Peacemaker, The (1997)Peacemaker, The (1997)Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964)Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964)Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964)Newton Boys, The (1998)Newton Boys, The (1998)Newton Boys, The (1998)Newton Boys, The (1998)Newton Boys, The (1998)Newton Boys, The (1998)House on Haunted Hill (1999)House on Haunted Hill (1999)House on Haunted Hill (1999)House on Haunted Hill (1999)Apt Pupil (1998)Apt Pupil (1998)Mr. Death: The Rise and Fall of Fred A. Leuchter, Jr. (1999)Fast, Cheap & Out of Control (1997)Welcome To Sarajevo (1997)Welcome To Sarajevo (1997)Species II (1998)Species II (1998)Species II (1998)Species II (1998)Species II (1998)Wild Bunch, The (1969)Wild Bunch, The (1969)Wild Bunch, The (1969)Wild Bunch, The (1969)Wild Bunch, The (1969)Wild Bunch, The (1969)Final Destination (2000)Final Destination (2000)Final Destination (2000)Palmetto (1998)Palmetto (1998)Palmetto (1998)Palmetto (1998)Big Hit, The (1998)Big Hit, The (1998)Big Hit, The (1998)Big Hit, The (1998)Big Hit, The (1998)Big Hit, The (1998)As Good As It Gets (1997)As Good As It Gets (1997)As Good As It Gets (1997)Deep Impact (1998)Deep Impact (1998)Deep Impact (1998)When We Were Kings (1996)Arlington Road (1999)Arlington Road (1999)Arlington Road (1999)Siege, The (1998)Siege, The (1998)Courage Under Fire (1996)Courage Under Fire (1996)Courage Under Fire (1996)Titanic (1997)Titanic (1997)Titan A.E. (2000)Titan A.E. (2000)Titan A.E. (2000)Titan A.E. (2000)Independence Day (1996)Independence Day (1996)Virus (1999)Virus (1999)Virus (1999)Virus (1999)Wizard of Oz, The (1939)Wizard of Oz, The (1939)Wizard of Oz, The (1939)Three Kings (1999)Three Kings (1999)Three Kings (1999)Three Kings (1999)Three Kings (1999)Three Kings (1999)Three Kings (1999)Three Kings (1999)Perfect Blue (1997/I)Perfect Blue (1997/I)Perfect Blue (1997/I)Patriot, The (2000)Patriot, The (2000)Patriot, The (2000)Godzilla (1998)Godzilla (1998)Godzilla (1998)Thirteenth Floor, The (1999)Thirteenth Floor, The (1999)Thirteenth Floor, The (1999)Dogma (1999)Dogma (1999)Galaxy Quest (1999)Galaxy Quest (1999)Galaxy Quest (1999)Galaxy Quest (1999)Alien: Resurrection (1997)Alien: Resurrection (1997)Alien: Resurrection (1997)Species II (1998)Species II (1998)Species II (1998)Mars Attacks! (1996)Mars Attacks! (1996)Mars Attacks! (1996)Mission to Mars (2000)Mission to Mars (2000)Mission to Mars (2000)Mission to Mars (2000)Scream 2 (1997)Scream 2 (1997)Scream 2 (1997)Scream 2 (1997)Violon rouge, Le (1998)Violon rouge, Le (1998)Violon rouge, Le (1998)Psycho (1998)Psycho (1998)Tombstone (1993)Tombstone (1993)Tombstone (1993)Wyatt Earp (1994)Tombstone (1993)Tombstone (1993)Tombstone (1993)Spanish Prisoner, The (1997)Spanish Prisoner, The (1997)Spanish Prisoner, The (1997)Braveheart (1995)Braveheart (1995)Braveheart (1995)Braveheart (1995)Braveheart (1995)Conspiracy Theory (1997)Conspiracy Theory (1997)Conspiracy Theory (1997)Conspiracy Theory (1997)Mortal Kombat: Annihilation (1997)Mortal Kombat: Annihilation (1997)Mortal Kombat: Annihilation (1997)Mortal Kombat: Annihilation (1997)Mortal Kombat: Annihilation (1997)Mortal Kombat: Annihilation (1997)Topsy-Turvy (1999)Topsy-Turvy (1999)Jackie Brown (1997)Jackie Brown (1997)Pulp Fiction (1994)Pulp Fiction (1994)Pulp Fiction (1994)Pulp Fiction (1994)Go (1999)Go (1999)Blast from the Past (1999)Blast from the Past (1999)Bedazzled (2000)Bedazzled (2000)Face/Off (1997)Face/Off (1997)Face/Off (1997)Shiloh 2: Shiloh Season (1999)Shiloh 2: Shiloh Season (1999)Shiloh 2: Shiloh Season (1999)Battlefield Earth (2000)Battlefield Earth (2000)Battlefield Earth (2000)Battlefield Earth (2000)American Beauty (1999)American Beauty (1999)Tomorrow Never Dies (1997)Tomorrow Never Dies (1997)Tomorrow Never Dies (1997)World Is Not Enough, The (1999)World Is Not Enough, The (1999)World Is Not Enough, The (1999)World Is Not Enough, The (1999)Trekkies (1997)Trekkies (1997)Beavis and Butt-head Do America (1996)Beavis and Butt-head Do America (1996)Beavis and Butt-head Do America (1996)Beavis and Butt-head Do America (1996)Almost Famous (2000)Almost Famous (2000)Almost Famous (2000)Tarzan (1999)Tarzan (1999)Mulan (1998)Mulan (1998)Mulan (1998)Mulan (1998)Mulan (1998)Mulan (1998)Mulan (1998)Mulan (1998)Mulan (1998)Mulan (1998)Con Air (1997)Con Air (1997)Spanish Prisoner, The (1997)Spanish Prisoner, The (1997)Spanish Prisoner, The (1997)Beauty and the Beast (1991)Beauty and the Beast (1991)Little Mermaid, The (1989)Little Mermaid, The (1989)Little Mermaid, The (1989)Little Mermaid, The (1989)Pocahontas (1995)Pocahontas (1995)Pocahontas (1995)Lion King, The (1994)Lion King, The (1994)Lion King, The (1994)Aladdin (1992)Aladdin (1992)Aladdin (1992)Aladdin (1992)Fantasia/2000 (1999)Fantasia/2000 (1999)Fantasia/2000 (1999)Fantasia/2000 (1999)Stuart Little (1999)Stuart Little (1999)Stuart Little (1999)Stuart Little (1999)Small Soldiers (1998)Small Soldiers (1998)Small Soldiers (1998)Small Soldiers (1998)Toy Story (1995)Toy Story (1995)Toy Story (1995)Toy Story 2 (1999)Toy Story 2 (1999)Toy Story 2 (1999)Chicken Run (2000)Chicken Run (2000)Lethal Weapon 4 (1998)Lethal Weapon 4 (1998)Lethal Weapon 4 (1998)Lethal Weapon 4 (1998)Adventures of Rocky & Bullwinkle, The (2000)Adventures of Rocky & Bullwinkle, The (2000)Ronin (1998)Ronin (1998)Ronin (1998)Ronin (1998)Ronin (1998)Ronin (1998)Full Metal Jacket (1987)Full Metal Jacket (1987)Full Metal Jacket (1987)Born on the Fourth of July (1989)Born on the Fourth of July (1989)Heaven & Earth (1993)Heaven & Earth (1993)Heaven & Earth (1993)Heaven & Earth (1993)Heaven & Earth (1993)Heaven & Earth (1993)Thomas Crown Affair, The (1999)Thomas Crown Affair, The (1999)Forces of Nature (1999)Forces of Nature (1999)Rules of Engagement (2000)Forces of Nature (1999)Forces of Nature (1999)Powder (1995)Powder (1995)Powder (1995)Powder (1995)Star Wars (1977)Star Wars (1977)Star Wars (1977)Star Wars (1977)Star Wars: Episode I - The Phantom Menace (1999)Star Wars: Episode I - The Phantom Menace (1999)Star Wars: Episode I - The Phantom Menace (1999)Hollow Man (2000)Hollow Man (2000)Hollow Man (2000)Cruel Intentions (1999)Cruel Intentions (1999)Babe: Pig in the City (1998)Babe: Pig in the City (1998)Star Trek: First Contact (1996)Star Trek: First Contact (1996)Star Trek: Insurrection (1998)Star Trek: Insurrection (1998)Road to El Dorado, The (2000)Road to El Dorado, The (2000)Whole Nine Yards, The (2000)Whole Nine Yards, The (2000)Whole Nine Yards, The (2000)Whole Nine Yards, The (2000)Pitch Black (2000)Pitch Black (2000)Pitch Black (2000)Pitch Black (2000)Beach, The (2000)Beach, The (2000)I Still Know What You Did Last Summer (1998)I Still Know What You Did Last Summer (1998)I Know What You Did Last Summer (1997)I Know What You Did Last Summer (1997)I Know What You Did Last Summer (1997)Devil’s Advocate, The (1997)Devil’s Advocate, The (1997)Devil’s Advocate, The (1997)Astronaut’s Wife, The (1999)Astronaut’s Wife, The (1999)Mighty Joe Young (1998)Mighty Joe Young (1998)Meet Joe Black (1998)Meet Joe Black (1998)Meet Joe Black (1998)Matrix, The (1999)Matrix, The (1999)Matrix, The (1999)Deep Blue Sea (1999)Deep Blue Sea (1999)Deep Blue Sea (1999)Deep Blue Sea (1999)Deep Blue Sea (1999)Deep Blue Sea (1999)Deep Blue Sea (1999)Deep Blue Sea (1999)Batman Returns (1992)Batman Returns (1992)Batman Returns (1992)Batman (1989)Batman (1989)Batman (1989)Batman & Robin (1997)Batman & Robin (1997)Batman & Robin (1997)Batman & Robin (1997)Batman & Robin (1997)Batman & Robin (1997)Batman Forever (1995)Batman Forever (1995)Batman Forever (1995)Spawn (1997)Spawn (1997)X Files, The (1998)X Files, The (1998)X Files, The (1998)Mystery Men (1999)Mystery Men (1999)Blade (1998)Blade (1998)Vampires (1998)Vampires (1998)Vampires (1998)Edtv (1999)Edtv (1999)Truman Show, The (1998)Truman Show, The (1998)Truman Show, The (1998)Truman Show, The (1998)Lost Highway (1997)Lost Highway (1997)Lost Highway (1997)Blue Velvet (1986)Blue Velvet (1986)Rushmore (1998)Rushmore (1998)Pi (1998)Pi (1998)Pi (1998)Pi (1998)Never Been Kissed (1999)Never Been Kissed (1999)American Pie (1999)She’s All That (1999)She’s All That (1999)Desperado (1995)Desperado (1995)Desperado (1995)Desperado (1995)Desperado (1995)Desperado (1995)Desperado (1995)Desperado (1995)Faculty, The (1998)Faculty, The (1998)Faculty, The (1998)True Crime (1999)True Crime (1999)True Crime (1999)True Crime (1999)True Crime (1999)True Crime (1999)Unforgiven (1992)Unforgiven (1992)Unforgiven (1992)High Noon (1952)High Noon (1952)Nurse Betty (2000)Nurse Betty (2000)Negotiator, The (1998)Negotiator, The (1998)Negotiator, The (1998)Negotiator, The (1998)Negotiator, The (1998)Negotiator, The (1998)Thin Red Line, The (1998)Thin Red Line, The (1998)Thin Red Line, The (1998)Thin Red Line, The (1998)Thin Red Line, The (1998)Thin Red Line, The (1998)Entrapment (1999)Entrapment (1999)Entrapment (1999)Entrapment (1999)Mask of Zorro, The (1998)Mask of Zorro, The (1998)Mask of Zorro, The (1998)Air Force One (1997)Air Force One (1997)Air Force One (1997)Gladiator (2000)Gladiator (2000)Gladiator (2000)Gladiator (2000)Evita (1996)Evita (1996)Mask, The (1994)Mask, The (1994)Mask, The (1994)Mask, The (1994)How the Grinch Stole Christmas (2000)How the Grinch Stole Christmas (2000)Mask, The (1994)Mask, The (1994)Mask, The (1994)Mask, The (1994)Man on the Moon (1999)Man on the Moon (1999)Man on the Moon (1999)Man on the Moon (1999)Frequency (2000)Frequency (2000)Frequency (2000)Frequency (2000)Frequency (2000)Frequency (2000)Twelve Monkeys (1995)Twelve Monkeys (1995)Twelve Monkeys (1995)Twelve Monkeys (1995)Twelve Monkeys (1995)Twelve Monkeys (1995)4 Little Girls (1997)October Sky (1999)October Sky (1999)

October Sky (1999)Bicentennial Man (1999)Bicentennial Man (1999)Bicentennial Man (1999)

Eye of the Beholder (1999)Eye of the Beholder (1999)

Eye of the Beholder (1999)Eye of the Beholder (1999)

Dinosaur (2000)

Dinosaur (2000)

Jurassic Park (1993)Jurassic Park (1993)Jurassic Park (1993)Jurassic Park (1993)Jurassic Park (1993)

South Park: Bigger, Longer and Uncut (1999)South Park: Bigger, Longer and Uncut (1999)South Park: Bigger, Longer and Uncut (1999)South Park: Bigger, Longer and Uncut (1999)South Park: Bigger, Longer and Uncut (1999)South Park: Bigger, Longer and Uncut (1999)Jurassic Park (1993)Jurassic Park (1993)Jurassic Park (1993)Jurassic Park (1993)Jurassic Park (1993)

Twister (1996)Twister (1996)

Twister (1996)Twister (1996)Urban Legend (1998)Urban Legend (1998)

Urban Legend (1998)Urban Legend (1998)

Shiloh 2: Shiloh Season (1999)Shiloh 2: Shiloh Season (1999)Shiloh 2: Shiloh Season (1999)Blazing Saddles (1974)Blazing Saddles (1974)Sphere (1998)Sphere (1998)Lone Star (1996)Lone Star (1996)Summer of Sam (1999)Summer of Sam (1999)Bringing Out the Dead (1999)Natural Born Killers (1994)Natural Born Killers (1994)Natural Born Killers (1994)Natural Born Killers (1994)Natural Born Killers (1994)Natural Born Killers (1994)There’s Something About Mary (1998)There’s Something About Mary (1998)City of Angels (1998)City of Angels (1998)City of Angels (1998)City of Angels (1998)City of Angels (1998)City of Angels (1998)Boiler Room (2000)Boiler Room (2000)Beyond the Mat (1999)Good Will Hunting (1997)Hot Shots! (1991)Hot Shots! (1991)Lone Star (1996)Lone Star (1996)Beauty and the Beast (1991)Beauty and the Beast (1991)My Best Friend’s Wedding (1997)My Best Friend’s Wedding (1997)For Love of the Game (1999)For Love of the Game (1999)For Love of the Game (1999)For Love of the Game (1999)Life and Times of Hank Greenberg, The (1998)Life and Times of Hank Greenberg, The (1998)Reindeer Games (2000)Reindeer Games (2000)Reindeer Games (2000)Reindeer Games (2000)Legends of the Fall (1994)Legends of the Fall (1994)Legends of the Fall (1994)Legends of the Fall (1994)Legends of the Fall (1994)Legends of the Fall (1994)Legends of the Fall (1994)Legends of the Fall (1994)Legends of the Fall (1994)Conspiracy Theory (1997)Conspiracy Theory (1997)Conspiracy Theory (1997)Conspiracy Theory (1997)You’ve Got Mail (1998)You’ve Got Mail (1998)You’ve Got Mail (1998)You’ve Got Mail (1998)City Slickers II: The Legend of Curly’s Gold (1994)City Slickers II: The Legend of Curly’s Gold (1994)City Slickers II: The Legend of Curly’s Gold (1994)City Slickers II: The Legend of Curly’s Gold (1994)Analyze This (1999)Analyze This (1999)Analyze This (1999)Analyze This (1999)Little Women (1994)Little Women (1994)Little Women (1994)Little Women (1994)Man in the Iron Mask, The (1998)Man in the Iron Mask, The (1998)Man in the Iron Mask, The (1998)Stop Making Sense (1984)Fight Club (1999)Fight Club (1999)Fight Club (1999)Love’s Labour’s Lost (2000)Love’s Labour’s Lost (2000)Love’s Labour’s Lost (2000)Richard III (1995)Richard III (1995)Richard III (1995)Richard III (1995)Michael (1996)Michael (1996)Michael (1996)Backbeat (1993)Backbeat (1993)Wag the Dog (1997)Notting Hill (1999)Notting Hill (1999)Notting Hill (1999)Notting Hill (1999)Notting Hill (1999)Notting Hill (1999)Erin Brockovich (2000)Starship Troopers (1997)Starship Troopers (1997)Starship Troopers (1997)Men in Black (1997)Men in Black (1997)Men in Black (1997)Men in Black (1997)Men in Black (1997)Men in Black (1997)Enemy of the State (1998)Enemy of the State (1998)Mimic (1997)Mimic (1997)Mimic (1997)Horse Whisperer, The (1998)Horse Whisperer, The (1998)PokØmon the First Movie: Mewtwo Strikes Back (1999)Everyone Says I Love You (1996)Everyone Says I Love You (1996)Everyone Says I Love You (1996)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Mononoke Hime (1997)Election (1999)Election (1999)Cruise, The (1998/I)Walk in the Clouds, A (1995)Walk in the Clouds, A (1995)Walk in the Clouds, A (1995)Bone Collector, The (1999)Bone Collector, The (1999)Bone Collector, The (1999)Cruise, The (1998/I)Mission: Impossible II (2000)Mission: Impossible II (2000)Mission: Impossible II (2000)Mission: Impossible II (2000)Mars Attacks! (1996)Mars Attacks! (1996)Mars Attacks! (1996)Magnolia (1999)Scream (1996)Scream (1996)Scream (1996)What Dreams May Come (1998)What Dreams May Come (1998)Rounders (1998)Rounders (1998)Forrest Gump (1994)Forrest Gump (1994)Forrest Gump (1994)8MM (1999)8MM (1999)8MM (1999)8MM (1999)8MM (1999)8MM (1999)8MM (1999)8MM (1999)Postman, The (1997)Postman, The (1997)Postman, The (1997)Postman, The (1997)General’s Daughter, The (1999)General’s Daughter, The (1999)General’s Daughter, The (1999)General’s Daughter, The (1999)General’s Daughter, The (1999)General’s Daughter, The (1999)Watcher, The (2000)Watcher, The (2000)Watcher, The (2000)Watcher, The (2000)U-571 (2000)U-571 (2000)U-571 (2000)U-571 (2000)My Best Friend’s Wedding (1997)My Best Friend’s Wedding (1997)Strange Days (1995)Strange Days (1995)Strange Days (1995)Strange Days (1995)Strange Days (1995)Strange Days (1995)Scream (1996)Scream (1996)Scream (1996)Beach, The (2000)Beach, The (2000)U-571 (2000)U-571 (2000)U-571 (2000)U-571 (2000)Mimic (1997)Mimic (1997)Mimic (1997)Edge, The (1997)Edge, The (1997)Edge, The (1997)Edge, The (1997)Messenger: The Story of Joan of Arc, The (1999)Messenger: The Story of Joan of Arc, The (1999)Messenger: The Story of Joan of Arc, The (1999)Messenger: The Story of Joan of Arc, The (1999)Fifth Element, The (1997)Fifth Element, The (1997)Fifth Element, The (1997)Fifth Element, The (1997)Fifth Element, The (1997)Fifth Element, The (1997)Sixth Sense, The (1999)Sixth Sense, The (1999)Sixth Sense, The (1999)Unbreakable (2000)Unbreakable (2000)Unbreakable (2000)Soldier (1998)Soldier (1998)Crow, The (1994)Crow, The (1994)Crow, The (1994)Crow, The (1994)Crow, The (1994)Crow, The (1994)Crow, The (1994)Crow, The (1994)Dark City (1998)Dark City (1998)Dark City (1998)Dark City (1998)Dark City (1998)Dark City (1998)Vita Ł bella, La (1997)Vita Ł bella, La (1997)Welcome To Sarajevo (1997)Welcome To Sarajevo (1997)Final Destination (2000)Final Destination (2000)Final Destination (2000)As Good As It Gets (1997)As Good As It Gets (1997)As Good As It Gets (1997)Drowning Mona (2000)Drowning Mona (2000)Siege, The (1998)Siege, The (1998)Titanic (1997)Titanic (1997)Wizard of Oz, The (1939)Wizard of Oz, The (1939)Wizard of Oz, The (1939)Three Kings (1999)Three Kings (1999)Three Kings (1999)Three Kings (1999)Independence Day (1996)Independence Day (1996)Thirteenth Floor, The (1999)Thirteenth Floor, The (1999)Thirteenth Floor, The (1999)Game, The (1997)Game, The (1997)What Planet Are You From? (2000)What Planet Are You From? (2000)PokØmon the First Movie: Mewtwo Strikes Back (1999)Psycho (1998)Psycho (1998)Braveheart (1995)Braveheart (1995)Braveheart (1995)Braveheart (1995)Braveheart (1995)Payback (1999)Payback (1999)Payback (1999)Se7en (1995)Se7en (1995)Se7en (1995)Se7en (1995)Go (1999)Go (1999)Shaft (2000)Shaft (2000)Shaft (2000)Shaft (2000)Tomorrow Never Dies (1997)Tomorrow Never Dies (1997)Tomorrow Never Dies (1997)Midnight in the Garden of Good and Evil (1997)Midnight in the Garden of Good and Evil (1997)Avengers, The (1998)Avengers, The (1998)Anastasia (1997)Anastasia (1997)Tigger Movie, The (2000)Tigger Movie, The (2000)Nightmare Before Christmas, The (1993)Nightmare Before Christmas, The (1993)Nightmare Before Christmas, The (1993)Nightmare Before Christmas, The (1993)Nightmare Before Christmas, The (1993)Toy Story 2 (1999)Toy Story 2 (1999)Toy Story 2 (1999)Lethal Weapon 4 (1998)Lethal Weapon 4 (1998)Lethal Weapon 4 (1998)Lethal Weapon 4 (1998)Mission: Impossible (1996)Mission: Impossible (1996)Mission: Impossible (1996)Full Metal Jacket (1987)Full Metal Jacket (1987)Full Metal Jacket (1987)Dogma (1999)Forces of Nature (1999)Forces of Nature (1999)Star Wars (1977)Star Wars (1977)Star Wars (1977)Star Wars (1977)Star Wars (1977)Star Wars (1977)Star Wars (1977)Star Wars (1977)Babe: Pig in the City (1998)Babe: Pig in the City (1998)Star Trek: Insurrection (1998)Star Trek: Insurrection (1998)Star Trek: First Contact (1996)Star Trek: First Contact (1996)I Still Know What You Did Last Summer (1998)I Still Know What You Did Last Summer (1998)Devil’s Advocate, The (1997)Devil’s Advocate, The (1997)Devil’s Advocate, The (1997)Astronaut’s Wife, The (1999)Astronaut’s Wife, The (1999)Matrix, The (1999)Matrix, The (1999)Matrix, The (1999)Batman (1989)Batman (1989)Batman (1989)Batman & Robin (1997)Batman & Robin (1997)Batman & Robin (1997)Hot Shots! (1991)Hot Shots! (1991)Mystery Men (1999)Mystery Men (1999)Pleasantville (1998)Pleasantville (1998)Pleasantville (1998)Lost Highway (1997)Lost Highway (1997)Lost Highway (1997)Never Been Kissed (1999)Never Been Kissed (1999)10 Things I Hate About You (1999)10 Things I Hate About You (1999)Hoop Dreams (1994)True Crime (1999)True Crime (1999)True Crime (1999)Mickey Blue Eyes (1999)Mickey Blue Eyes (1999)Mickey Blue Eyes (1999)Negotiator, The (1998)Negotiator, The (1998)Negotiator, The (1998)

Mask, The (1994)Mask, The (1994)Mask, The (1994)Mask, The (1994)Frequency (2000)Frequency (2000)Frequency (2000)Emperor’s New Groove, The (2000)Emperor’s New Groove, The (2000)Last Man Standing (1996)Last Man Standing (1996)Last Man Standing (1996)

Jurassic Park (1993)Jurassic Park (1993)Jurassic Park (1993)Jurassic Park (1993)Jurassic Park (1993)

Lost World: Jurassic Park, The (1997)Lost World: Jurassic Park, The (1997)Lost World: Jurassic Park, The (1997)Lost World: Jurassic Park, The (1997)Lost World: Jurassic Park, The (1997)

Double Jeopardy (1999)Double Jeopardy (1999)Double Jeopardy (1999)Double Jeopardy (1999)

Shiloh 2: Shiloh Season (1999)Shiloh 2: Shiloh Season (1999)Shiloh 2: Shiloh Season (1999)

4 Little Girls (1997)

Bringing Out the Dead (1999)There’s Something About Mary (1998)There’s Something About Mary (1998)Boiler Room (2000)Boiler Room (2000)Boiler Room (2000)Boiler Room (2000)Buono, il brutto, il cattivo, Il (1966)Buono, il brutto, il cattivo, Il (1966)Truman Show, The (1998)Truman Show, The (1998)Truman Show, The (1998)Truman Show, The (1998)

Reindeer Games (2000)Reindeer Games (2000)Air Force One (1997)Air Force One (1997)Air Force One (1997)Air Force One (1997)Air Force One (1997)Air Force One (1997)Air Force One (1997)Air Force One (1997)Analyze This (1999)Analyze This (1999)Man in the Iron Mask, The (1998)Man in the Iron Mask, The (1998)Man in the Iron Mask, The (1998)Stop Making Sense (1984)Blair Witch Project, The (1999)Blair Witch Project, The (1999)Simple Plan, A (1998)Simple Plan, A (1998)Simple Plan, A (1998)Notting Hill (1999)Notting Hill (1999)Notting Hill (1999)Erin Brockovich (2000)Mickey Blue Eyes (1999)Mickey Blue Eyes (1999)Mickey Blue Eyes (1999)Perfect Blue (1997/I)Perfect Blue (1997/I)Perfect Blue (1997/I)Eyes of Tammy Faye, The (2000)Election (1999)Cop Land (1997)Cop Land (1997)Battlefield Earth (2000)Battlefield Earth (2000)What Dreams May Come (1998)What Dreams May Come (1998)What Dreams May Come (1998)What Dreams May Come (1998)Stir of Echoes (1999)Stir of Echoes (1999)Stir of Echoes (1999)Stir of Echoes (1999)Cell, The (2000)Cell, The (2000)Cell, The (2000)English Patient, The (1996)English Patient, The (1996)Talented Mr. Ripley, The (1999)Talented Mr. Ripley, The (1999)Beach, The (2000)Beach, The (2000)Being John Malkovich (1999)Being John Malkovich (1999)Fifth Element, The (1997)Fifth Element, The (1997)Fifth Element, The (1997)Fifth Element, The (1997)Fifth Element, The (1997)Fifth Element, The (1997)Insider, The (1999)Insider, The (1999)Dark City (1998)Dark City (1998)Dark City (1998)Schindler’s List (1993)Schindler’s List (1993)Hi-Lo Country, The (1998)Hi-Lo Country, The (1998)Hi-Lo Country, The (1998)Hi-Lo Country, The (1998)From Here to Eternity (1953)From Here to Eternity (1953)From Here to Eternity (1953)Mediterraneo (1991)Mediterraneo (1991)Game, The (1997)Game, The (1997)PokØmon the First Movie: Mewtwo Strikes Back (1999)X-Men (2000)X-Men (2000)X-Men (2000)X-Men (2000)Grease (1978)Grease (1978)Grease (1978)Avengers, The (1998)Avengers, The (1998)Hercules (1997)Hercules (1997)Hercules (1997)Hercules (1997)Gone in Sixty Seconds (2000)Gone in Sixty Seconds (2000)Armageddon (1998)Armageddon (1998)Armageddon (1998)Armageddon (1998)20 Dates (1998)20 Dates (1998)20 Dates (1998)Trekkies (1997)Perfect Storm, The (2000)Perfect Storm, The (2000)Perfect Storm, The (2000)Borrowers, The (1997)Borrowers, The (1997)Borrowers, The (1997)Borrowers, The (1997)Pleasantville (1998)Pleasantville (1998)Pleasantville (1998)What Lies Beneath (2000)What Lies Beneath (2000)What Lies Beneath (2000)Contact (1997)Contact (1997)Contact (1997)Contact (1997)Contact (1997)Great Expectations (1998)Great Expectations (1998)Bowfinger (1999)Emperor’s New Groove, The (2000)Emperor’s New Groove, The (2000)

Last Man Standing (1996)Last Man Standing (1996)Last Man Standing (1996)

Lost World: Jurassic Park, The (1997)Lost World: Jurassic Park, The (1997)Lost World: Jurassic Park, The (1997)Lost World: Jurassic Park, The (1997)Lost World: Jurassic Park, The (1997)

Double Jeopardy (1999)Double Jeopardy (1999)Double Jeopardy (1999)Double Jeopardy (1999)

Kiss the Girls (1997)Kiss the Girls (1997)Kiss the Girls (1997)Kiss the Girls (1997)Blues Brothers 2000 (1998)Blues Brothers 2000 (1998)Blues Brothers 2000 (1998)Blues Brothers 2000 (1998)Event Horizon (1997)Event Horizon (1997)Event Horizon (1997)Supernova (2000)Supernova (2000)Supernova (2000)Blair Witch Project, The (1999)Blair Witch Project, The (1999)Lost in Space (1998)Lost in Space (1998)Lost in Space (1998)Contact (1997)Contact (1997)Contact (1997)Contact (1997)Contact (1997)Contact (1997)Contact (1997)Contact (1997)Contact (1997)Contact (1997)End of Days (1999)End of Days (1999)End of Days (1999)English Patient, The (1996)English Patient, The (1996)Gattaca (1997)Gattaca (1997)Gattaca (1997)Gattaca (1997)Gattaca (1997)Gattaca (1997)Bent (1997)Bent (1997)Mediterraneo (1991)Mediterraneo (1991)13th Warrior, The (1999)13th Warrior, The (1999)13th Warrior, The (1999)13th Warrior, The (1999)13th Warrior, The (1999)Last of the Mohicans, The (1992)Last of the Mohicans, The (1992)Last of the Mohicans, The (1992)Walk in the Clouds, A (1995)Walk in the Clouds, A (1995)Walk in the Clouds, A (1995)20 Dates (1998)20 Dates (1998)20 Dates (1998)Richard III (1995)Richard III (1995)Scary Movie (2000)Scary Movie (2000)Scary Movie (2000)X-Men (2000)X-Men (2000)

Bowfinger (1999)

U.S. Marshals (1998)U.S. Marshals (1998)Se7en (1995)Se7en (1995)Se7en (1995)Se7en (1995)Supernova (2000)Supernova (2000)Supernova (2000)Lost in Space (1998)Lost in Space (1998)Lost in Space (1998)Stigmata (1999)Stigmata (1999)Stigmata (1999)Stigmata (1999)Crumb (1994)Geronimo: An American Legend (1993)Geronimo: An American Legend (1993)Parapluies de Cherbourg, Les (1964)Parapluies de Cherbourg, Les (1964)Parapluies de Cherbourg, Les (1964)

Scary Movie (2000)Scary Movie (2000)Scary Movie (2000)Game, The (1997)Game, The (1997)

Figure 6: Mapping a new text.

As illustrated in Fig. 6, the HSOM mightalso be used to classify an unknown text bydisplaying its relationship to a previously ac-quired document collection. In this examplean unknown review text for the film “Juras-sic Park” was mapped. The map was thenzoomed to that node which most closely re-sembled the given input text, which in thiscase was another review describing the samefilm. Note, that the neighborhood is occu-pied by reviews describing the sequel “TheLost World”, respectively the “Dinosaurs”animation. By mapping a complete unknowndocument collection to a previously formedHSOM, relevant text documents can be discovered. In Fig. 7 the HSOM is usedas a filter to display only those documents which belong to a semantic region ofinterest.

Prince of Egypt, The (1998)

Wild Wild West (1999)Bug’s Life, A (1998)Antz (1998)

Mononoke Hime (1997)Iron Giant, The (1999)

Nightmare Before Christmas, The (1993)

Shanghai Noon (2000)

Maverick (1994)Titan A.E. (2000)

Beavis and Butt-head Do America (1996)Tarzan (1999)Mulan (1998)

Beauty and the Beast (1991)Little Mermaid, The (1989)Pocahontas (1995)Lion King, The (1994)Aladdin (1992)Fantasia/2000 (1999)

Toy Story (1995)Toy Story 2 (1999)Chicken Run (2000)

Road to El Dorado, The (2000)

Dinosaur (2000)South Park: Bigger, Longer and Uncut (1999)Blazing Saddles (1974)Parapluies de Cherbourg, Les (1964)

City Slickers II: The Legend of Curly’s Gold (1994)

Anastasia (1997)Tigger Movie, The (2000)

Toy Story (1995)

Emperor’s New Groove, The (2000)

Hercules (1997)

(a)

Prince of Egypt, The (1998)Wild Wild West (1999)Bug’s Life, A (1998)Antz (1998)Mononoke Hime (1997)Iron Giant, The (1999)Nightmare Before Christmas, The (1993)Shanghai Noon (2000)

Maverick (1994)

Titan A.E. (2000)

Beavis and Butt-head Do America (1996)Tarzan (1999)

Mulan (1998)

Beauty and the Beast (1991)Little Mermaid, The (1989)

Pocahontas (1995)Lion King, The (1994)

Aladdin (1992)Fantasia/2000 (1999)

Toy Story (1995)Toy Story 2 (1999)

Chicken Run (2000)Road to El Dorado, The (2000)

Dinosaur (2000)South Park: Bigger, Longer and Uncut (1999)Blazing Saddles (1974)Parapluies de Cherbourg, Les (1964)City Slickers II: The Legend of Curly’s Gold (1994)

Anastasia (1997)

Tigger Movie, The (2000)

Toy Story (1995)

Emperor’s New Groove, The (2000)

Hercules (1997)

(b)

Prince of Egypt, The (1998)

Wild Wild West (1999)

Bug’s Life, A (1998)Antz (1998)

Mononoke Hime (1997)Iron Giant, The (1999)

Nightmare Before Christmas, The (1993)Shanghai Noon (2000)

Maverick (1994)Titan A.E. (2000)Beavis and Butt-head Do America (1996)Tarzan (1999)Mulan (1998)Beauty and the Beast (1991)Little Mermaid, The (1989)Pocahontas (1995)Lion King, The (1994)Aladdin (1992)Fantasia/2000 (1999)Toy Story (1995)Toy Story 2 (1999)Chicken Run (2000)Road to El Dorado, The (2000)Dinosaur (2000)South Park: Bigger, Longer and Uncut (1999)Blazing Saddles (1974)Parapluies de Cherbourg, Les (1964)City Slickers II: The Legend of Curly’s Gold (1994)

Anastasia (1997)Tigger Movie, The (2000)Toy Story (1995)Emperor’s New Groove, The (2000)

Hercules (1997)

(c)

Figure 7: Discovering of relevant documents in whole collections. In this example anunknown text collection is mapped onto the HSOM, but only those items are visualizedwhich belong to a selected category, in this case animation movies. The central view in(a) points to a set of document clusters, which can be interactively zoom into. In (b)the largest cluster has been moved into focus. It mainly shows Disney animations andfilms from the “Toy story” series a bit farther down. In (c) the cluster in the top leftcontains “A Bug’s Life” and “Antz”, whereas the cluster in the bottom right belongsto movies connected to Japanese animations.

5 Discussion

Our results show that the HSOM is not only applicable to automated text cat-egorization, but also specifically well suited to support “semantic browsing” inlarge document collections. Our first experiments indicate that the HSOM is ableto exploit the peculiar geometric properties of hyperbolic space to successfullycompress complex semantic relationships between text documents onto a twodimensional projection space. Additionally, the use of hyperbolic lattice topol-ogy for the arrangement of the HSOM nodes offers new and highly attractivefeatures for interactive navigation in this way. Large document databases canbe inspected at a glance while the HSOM provides additional information whichwas captured during a previous training step, allowing e. g. to rapidly visualizerelationships between new documents and previously acquired collections.

Future work will address more sophisticated visualization strategies based onthe new approach, as well as the evaluation for other widely used text collections,such as Reuters, Ohsumed or Pubmed.

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