Multi-Day and Multi-Stay Travel Planning using Geo- Tagged Photos

The Problem

Nov 5, 2013

GEOCROWD 2013

Xun Li

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Related Work in Geo-tagged Photos Research

Exploring landmarks or attraction places

“k-means” mean shift density based clustering hierarchical clustering

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Mining travel patterns from geo-tagged photos

Making travel recommendations/plans based on geo-tagged photos

weighted lines flow maps traffic flowsplotting travel routes

• One-day travel planning• Multi-day travel planning

Related Work in Operational Research

Orienteering Problem

• Given a set of attractions and a time budget, find a tour to maximize the collected scores from selected attractions

Team Orienteering Problem (TOP) with Time Window(TOPTW)

• Given a set of attractions and a time budget, send out several teams to find a set of tours to maximize the collected scores from selected attractions

• TOP problem plus setting up attractions with different time windows

Algorithms:

• Heuristic solutions (e.g. dynamic programming, greedy algorithm, iterated local optimum search )

Limitations:

• Travel attractions are from existed resources (e.g. tourist offices)• Attractiveness scores of POIs are predefined with categorical scores according to the types of attractions (e.g. museum, archaeology, nature etc.)• Correlations between POIs are not considered. 4

Research Problem

Automatically recommend multi-day and multi-stay travel plan to travellers based on travel knowledge that mined from Geo-tagged Photos

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• Integrates Geo-tagged Photos research with latest techniques in operational research

• Driven by rich travel information mined from geo-tagged photos:

• Points of interest, attractive score, suggested visiting time, opening and closing time, travel recurrence weights

• Relevance• Tourism research and practice• Personal guide services

Framework

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Finding POIs from Geo-Tagged Photos

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Algorithm: Ordering Points To Identify the Clustering Structure• Density-based clustering• Hierarchical clustering structure

POI Properties: • Name: the peak (Mean Shift) is mapped to and labeled

using the nearest feature from a preloaded OSM data • Attractive Score Si : # of troutists• Suggested Visiting Time Ti : avg(tlast_photo-tfirst_photo)• Time Window [Otime>8am , Ctime<6pm]i :

[min{tfirst_photo}, max{tlast_photo} ]

Travel Information and Travel Graph Model

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Travel Information:• Traveling time between POIs: using OSM data and

Open Source Routing Machine System (OSRMS, Luxenet. al. 2011)

• Traveling weights and Travel Graph Model:Reconstruct individual travel route

Travel graph model

Recurrence weight of sub-trip

Multi-day and Multi-stay Travel Planning using Geo-tagged Photos

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A Heuristic Solution

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A modified Iterative Local Search based heuristic algorithm to solve the multi-day and multi-stay travel plan problem• A variant of TSP problem (NP)• Approximate optimal solution as fast as possible

Algorithm• A variant of TSP problem (NP)• Approximate optimal solution as fast as possible

Heuristic Solution—Construct Step

Initialize tour with virtual POIs• Virtual POI: no location information

Inserting POIi between POIi and POIk

• Find best candidate• : reoccurring travel weights•

• Filtering:

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Heuristic Solution—Shake Step

Shake to remove a set of selected POIs from each sub-tour• Proved in [] as a good technique to explore the entire

solution space and correct earlier mistake solution

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Experiments

Application area• Australia (Sydney)• Tourism industry contributes

3% GDP (2011)• 5.9 million international

tourists (2011)Data:

• 118,736 geo-tagged photos contributed by 4,920 registered Internet users in Panoramio.com

• Average 24 geo-tagged photos per user

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Results

• 2,135 POIs in Australia

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OPTICS Result POI and Travel Patterns

Results

A 2-day tourist trip itinerary, which starts and ends at Sydney International Airport

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Results

The detail of the 2-day tourist trip itinerary is shown below:

Day 1 (pink route): start from Sydney International Airport at 8am; drive about 0.12 hours to Chinese Garden of Friendship at 8:20, spend 1 hour there;

drive 0.01 hours to Sydney Town Hall at 9:30, spend about 2.4 hours there; drive 0.01 hours to Sydney Aquarium at 12:00, spend about 1.5 hours there; drive 0.03 hours to the Mercantile at 13:40, spend 3.2 hours there; drive 0.15 hours to the Gap Park at 16:50, spend 1 hour there; drive 0.14 hours to Sydney Harbor Bridge at 18:00, find a hotel nearby to stay.

Day 2 (green route):start from near Sydney Harbor Bridge at 8am, spend about 3.9 hours there;

drive 0.01 hours to Sydney Opera House at 11:50, spend about 3.9 hours there; drive 0.01 hours to Museum of Contemporary Art at 15:30 and spend about 1.9 hours there;

drive 0.15 hours to Sydney International Airport at 18:00.

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Results

A 4-day tourist trip itinerary, which starts and ends at Sydney International Airport

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Results

The detail of the 4-day tourist trip itinerary is shown below:Day 1 (pink route): start from Sydney International Airport at 8am;drive 0.15 hours to Customs House at 8:15, spend about 4.5 hours there;

drive 1.8 hours to The Giant Stairway at 14:45, spend about 1hour there;drive 0.01 hours to The Three Sisters at 15:40, spend about 1.5 hours there;drive 0.02 hours to Scenic World Blue Mountains at 16:50, spend about 1 hour there;

drive 1.8 hours to Sydney Aquarium, and find a hotel nearby to stayDay 2 (green route): start from Sydney Aquarium at 8am, spend about 1.7 hours there;

drive0.03 hours to Royal Botanic Gardens at 9:50, spend about 1.6 hours there;drive 0.03 hours to Milsons Point at 11:20, spend about 2.5 hours there;drive 0.01 hours to Olympic Pool North Sydney at 13:50, spend about 2.5 hours there;

drive 0.15 hours to The Gap Park at 16:35, spend about 1 hour there;drive 0.14 hours to Sydney Opera House, and find a hotel nearby to stay

Day 3 (blue route):start from Sydney Opera House at 8am, spend 4 hours there;

drive 0.01 hours to Sydney Visitors Information Centre at 12:00, spend about 4 hours there;drive 0.01 hours to Museum of Contemporary Art at 16:20, spend about 1 hours there;drive 0.03 hours to Chinese Garden of Friendship at 17:20, spend about 0.5 hour there;drive 0.05 hours to Sydney Harbour Bridge, and find a hotel nearby to stayDay 4 (light yellow route):start from Sydney Harbour Bridge at 8am, spend about 3.5 hours there;

drive 0.01 hours to the Mercantile at 11:30, spend about 3.2 hours there;drive 0.02 hours to the Cenotaph at 14:50, spend about 0.8 hours there;drive 0.01 hours to the Sydney Town Hall at 15:30, spend about 2.3 hours there;drive 0.13 hours to Sydney International Airport at 18:00.

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Validation

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Validation

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Conclusion

Main contribution• An Intelligent Tourist Trip Plan System

• Solve multi-day and multi-stay travel plan problem using modified ILS based heuristic algorithm

• More applicable to realistic problems than existing solutions• large Internet social media data• results visualization (travel patterns, travel plans)

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Future Work

ValidationSurvey

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Thanks!

The Problem

Nov 5, 2013

GEOCROWD 2013

Xun Li

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