Usability: Chapter 1

Organisation

Usability is the measure of the ease at which you can use a site for itsintended purpose.

Exercise I

Consider the following websites.

www.play247.com www.bn.com

www.cd-universe.com www.cheap-cds.com

www.amazon.com www.hmv.co.uk

www.crotchet.co.uk

These sites all sell CDs. Usability testing involves investigating these sites from thepoint of view of their effectiveness and ease-of-use. E.g. Consider the following:

What services do the sites provide? (shopping baskets, recommendations,searching, second-hand CDs, etc.)

How clearly are those services identified?

How easy are they to use?

How easy it is to move about the sites?

How easily do they allow you to...

Find a particular CDFind the latest CD by a particular artistFind the CDs released this week.Find a classical CD by a certain composer, conductorFind a CD with a certain song on it , ..... etc.

How much information do they provide about a particular CD? Soundsamples? Credits? Reviews?

How can you contact the company with a query (assuming you can)?

How much will a CD cost to buy when shipping and other costs arecalculated? How easy is it to find this information?

What payment schemes do the sites support? (e.g. credit cards, cash,etc. Payment via phone, fax, email, forms, etc.)

Exercise II

Do usability tests on the following sites:

www.ucc.ie www.cit.ie www.tcd.ie www.ucd.ie

Perform the following tasks and note your observations. Tasks include:

• finding out if they offer a course in multimedia

• finding the contact details for the head of the computer science (orequivalent) department

• check if the library has a certain book (if you can)

Observations would include

How many clicks did it take to find the information? I.e. how many pages didyou need to view?

How many wrong turns did you take when looking for the information? I.e.how many irrelevant pages did you view?

How easy was it to find out if the information exists on the site? I.e. If you can'tfind something, is it because it is not there or because you have not been ableto find where it is?

etc.

Organisation of Information on the Web

The information stored on a site can be organised in many different ways. Thisorganisation will effect the way in which information is retrieved and will thereforeeffect the usability of the site. Therefore, to better analyse the usability of a site weshould examine how the information contained in that site is organised.

Organisation Schemes

These are the ways in which the Information is presented to the user. The userneeds to understand these schemes in order to be able to use your site.

The main schemes are as follows:

Exact Schemes

These are well defined and mutually exclusive schemes.

These schemes give the user a definite way of finding the information theywant. When they arrive at your site there should be a clearly defined way offinding the information they require. An advantage of these schemes is thatthe user can easily find out if the information they are looking for exists on thesite or not because there should be only one place it can be.

Exact schemes tend to be one of the following:

Alphabetical

These schemes present the information in alphabetical order.

Chronological

Sites can also present data in chronological order. If you are seekingdata you can look it up under a specific date and/or time. This isparticularly useful for news and history sites.

Geographical

Geographical schemes allow us to organise data based on thegeographical locations that the data applies to. We can represent thelocations diagrammatically.

Ambiguous Schemes

Ambiguous schemes differ from exact schemes in that they are not mutuallyexclusive (i.e. there may be more than one path to the same information).

Topical

In topical schemes you use general topics to organise yourinformation/services. In this scheme, the same information can appearunder several topics. E.g. in a tourism site Dublin might appear underIreland and European Capital Cities.

Menus (such as the one below) are a common example of topicalschemes.

Task-Oriented

Task Oriented systems present the user with a selection of tasks theywish to perform rather than a category of information they are looking for(E.g. "Search the site", "find a course", "Log in", etc. )

Audience Specific

In audience specific schemes you lay out your information in categoriesbased on the audiences you intend to reach.

Metaphor-driven

Theses schemes use their audiences familiarity with some concept tohelp them find their way around a site (this is similar to the way modernoperating schemes use a desktop metaphor). In the example below thedesigner used the rooms of a shack as the metaphor for the types ofinformation on the site.

The website below uses its name ("The Asylum") as an inspiration for itsdesign. The main page is modelled on a reception area. Clicking on thehelp desk brings you to a help page, clicking on the map on the wallbrings you to the site map and so on.

Further into the site a corridor is also used as a metaphor with each roombeing a link to a relevant page.

Hybrid Schemes

Unfortunately, designers frequently mix up the schemes they use. Thecategories you are presented with can be any combination of topical, taskoriented, geographical, metaphor and audience specific schemes.

Example (Audience and Topical):

In the left hand menu in the example below we can see categories such as"Activity Groups" (which leads to a page about Activity Groups" - i.e. it is atopical category), "Science Policy" (which leads to a page about the SciencePolicy) and "Students". However, the Students category is not about students(a topical category). Instead it is for Students (an audience-based category).As a result of this Hybrid scheme a user will be confused by the menu. It islikely that students will assume the category is about students and ignore it.

Example: (Task-based and Topical)

This menu from the Amazon.com site has one task-based category and 3topical categories.

It could easily be change to a topical scheme by removing the task element(i.e. the notion of viewing.)

Or, similarly, we could convert it to a task-based system.

Organisational Structures

Organisational Structures are the ways in which the information is structured on yoursite. Organisation schemes show how the information on your site will be presented tothe user (with regard to content). Organisational Structures refer to the way the wholesite is organised as an entity for the purposes of navigation. The organisation schemeis then applied to that structure.

Hierarchy

This is probably the most common structure whereby the information on thesite is accessed by organisational layers. For example, If you go to a collegesite you are given several options, one of which might be the list ofdepartments. Choose a dept and the next page might contain a list of all thesubject taught in that dept, and so on. There are two main types of hierarchy:

Narrow and Deep

This type of hierarchy would occur as a result of fewer links oneach page. A consequence of this is that the user will have tofollow more links to find the information they are looking for.

Broad and Shallow

These hierarchies arise from having more links on each page. As aresult there are fewer links to follow.

The best sites usually aim for a balance between these twoapproaches. Narrow and Deep sites take longer to navigate (morelinks to follow) but are also easier to navigate (fewer options).Broad and Shallow sites can be more difficult to navigate (there aremore options to consider) but require fewer links to follow whenyou do find what you are looking for.

Hypertext

The hypertext approach uses a more ad-hoc approach to navigation. Eachpage contains a link to another when appropriate to the context, rather than asan organised navigation system. This is usually used in conjunction with oneof the other structures discussed here.

Relational Database Model

Many sites do not exist as static files stored in the file system of the server.Instead they are generated using the contents of a database. These sites canbe made to appear as if they are using one of the structures discussed above,but you would usually use a search engine interface to navigate the content.

Navigation Systems

Navigation systems are the web page components you use to find your way around asite.

Context

It is helpful to indicate to the user of your site some notion of where they are.It allows them to see the context of the page they are on. This is particularlyuseful if they arrived at the page via a search engine. This is normallyachieved with bread crumbs (a list of links showing the path to this particularpage. "Home > District > About This Site > Bread Crumbs" in the examplebelow).

Similarly, note how on the left hand menu, the page the user is currently onhas been highlighted (i.e. the "Bread Crumbs" page).

Hierarchical Navigation Systems

Hierarchical Navigation systems are the links that support the mainhierarchical structure of a site. In the example below we can see the mainbranches of the hierarchy (I.e. Department, Courses, Research, NoticeBoard and Local Homepage).

Global Navigation Systems

On most sites you can place a global navIgation system on every page. Thisconsists of links to the main pages of your site that users may wish to accessregardless of where they are in your site. In the examples below thenavigation bar at the top of the page appears on every page in the site(making it global).

Local Navigation Systems

Many websites contain sub-sites: a section of the site that has a separatelook and feel to the rest of the site. These sub-sites normally have anavigation system of their own. In the example above, the RTE news webpages use both the global navigation system ....

.... and a local one....

Ad Hoc Navigation

And ad hoc navigation system is one where links occur in the content of thepage as necessary. In the example below, words which refer to topics forwhich there are other web pages, are converted to links.

Integrated Navigation Elements

These are navigation elements built in to your web pages. They usuallysupport global or local navigation schemes.

Menu Bars

These are the most common integrated navigation component. A menubar can be graphical, textual or both.

Pull Down Menus

Pull Down (or Pop-up) menus take up a small amount of space on aweb page and are therefore particularly useful for representing the linksin sites with broad and shallow hierarchical structures.

Frames

Frames are another common navigation method but should be usedwith care as sites with frames can cause confusion with some users.

Remote Navigation Elements

These are navigation systems that are separate from the integrated systems.Normally they are given a web page of their own.

Table of Contents

Sometimes a user may not wish to go through the bother of navigatingyour entire site in search of relevant data. To save time you can providea listing of the contents of the site on a single page. A Table of Contentsis one way of doing this. It usually consists of a list of all the majortopics in the site which act as links to the relevant page. The list oftopics is normally structured in manner that reflects the organisationstructure of the site (normally a hierarchy). The example below (miss-labelled as a "Site Index") shows this.

Tables of Contents are also frequently (and incorrectly) called SiteMaps. Fortunately this causes little confusion as a site normally has onlyone remote navigation page and the labels "index", "table of contents"and "map" have become synonyms for that page (regardless of the typeof element it is).

Index

An index is (usually) a fuller listing of the contents of a site allowing forvarious levels of granularity. As with Tables of Contents, they areparticular useful for sites which would normally involve a lot ofnavigation in order to find specific information. Unlike Tables ofContents an index has no structure and is normally a flat alphabeticallist of the relevant keywords.

Site Map

Unfortunately most web sites now consider an index or table of contentsthe equivalent of a Site Map. However, a Site Map is supposed to agraphical representation of the contents of a site.

Guided Tour

If your site contains unique navigation elements or you want to makesure people can easily navigate (and use) your site, you can provide aguided tour, i.e. part of your site dedicated to explaining how to makethe most out of the site with regard to both function and navigation.

Searching Systems

Many sites allow access to their data via a search tool. These search tools shouldallow the user to find information in a way that is of use to them. Users usually carryout one of the following searches:

Known Item Searching

Looking up something you know is there.

E.g. .looking up stocks or currency conversion rates.

Existence Searching

Just checking if something is on the site

E.g. is there a Multimedia degree in a certain college.

Exploratory Searching

A search where you don't know what you are going to find

E.g. looking for jobs on a careers site.

Comprehensive Searching (research)

Finding out as much information as you can on a topic

E.g. looking up everything you can find on a certain company you arethinking of joining.

Different search engines can vary on any of the following factors:

They can return information in different formats

They can search using different criteria.

They can use different labels for the search button/link(E.g. "Search", "Go", etc.).

The interface to the search can appear in different locations on the page.

E.g.

UCC centre bottom

DCU left

TCD bottom (link, but no form)

UCD left

CIT lower right

Nielsen and Tahir found the following with regard the position of the search:

Upper Right 41%Upper Center 11%Upper Left 4%Middle Left 11%Lower Right 7%Lower Center 11%Lower Left 19%

Exercise III:

Examine a handful of sites of your choosing.

In each case:

Describe the Organisational Scheme

What type is it? What are its good features? Its bad?

Describe the Organisational Structure

What type is it? What are its good features? Its bad?

Describe the Navigation System(s)

What types are used? Are they useful?

Describe the Labelling System (see next chapter)

Are names well chosen?

Describe the Searching System

Does the site support searches? If not, does it need to? What functionality isprovided by the search? What functionality is it lacking?