Description of SOC Images –Variation amongst SOCOs?

1. Description of SOC Images –Variation amongst SOCOs? Chris Handy, Mariam Tariq & Khurshid Ahmad 1

2. Variation amongst SOCO’s? • Over the last 3-4 Round Tables, and at other occasions, we have asked our RT members to describe SoC Images. • One of the intentions was to see the level of agreement amongst different SOCO’s about individual images. Are SOCO’s always consistent? How does this affect retrieval? • A consistency of description will help in automatically indexing the images for later retrieval.

3. Variation amongst SOCO’s? • A consistency of description may be in the description of objects as well as the locationof the objects. • Description of an object, for us, includes, identification and further elaboration. Are SOCO’s always consistent? How does this affect retrieval?

4. Variation amongst SOCO’s? • We analysed a set of images of a crime scene described by 8 different SOCOs. • SOCOs typically identify, locate, and giveadditional informationin their description. • We separated each caption into 3-4 phrases. The first 2 phrases identify an object in the image: typically the first being generic the second more specific.

5. Variation amongst SOCO’s?

6. Variation amongst SOCO’s? Identification Step 1

7. Variation amongst SOCO’s? Identification Step 2

8. Variation amongst SOCO’s? Location

9. Variation amongst SOCO’s? Additional Information

10. Variation amongst SOCO’s?

11. Variation amongst SOCO’s? Identification Step 1

12. Variation amongst SOCO’s? Identification Step 2

13. Variation amongst SOCO’s? Location

14. Variation amongst SOCO’s? “Single story church in Dempsey road.” “View from Dempsey Road towards church (front and right view).” “View onto Dempsey road showing church to the left hand side.” “Front view of church on Dempsey Road.” “View of church on cornerof Dempsey Place.” “Entirety view front of church with Dempsey Road on right hand side as viewed from the front of the church.”

15. Variation in vocabulary • Data was tabulated to evaluate variation/consistency

16. Observations (1) • A variety of synonyms used by different SOCOs e.g. ’flagstone pathway’  ‘paved area’; ‘lawn’ ‘grass’  ‘green area’ • Also in spatial relationships; • e.g. ‘adjacent’  ‘next to’ Several observations made about the data in general. 16

17. Observations (2) • Broader (supertype)/ Narrower (subtype) used by different indexers; e.g. ‘building’  ‘church’. • SOCOs consistently more or less verbose. • Objects often given an attribute e.g. gate (closed). • Orientation information common: e.g. ‘View from’.

18. Observations (3) • If an object e.g. a clothed body appears in a number of different photographs –SOCOS tend to describe the clothing but will do so in captions related to different photographs. • Broader term used first followed by abbreviations or subtype; e.g. ‘church’  ‘building’ • Captions seem to consist of an average of 3 sub-phrases.

19. Conclusions (1) -Variation • There is evidence of indexer variation at the lexical level

20. Conclusions (2) -Variation • However at the conceptual level there is more consistency

21. Conclusions (3) -Queries • If there is variation at the lexical level in indexing it may be reasonable to suppose that there will be variation in querying. • It may therefore be helpful to have some form of query expansion. This should help recall with variation in indexing and querying, but may make precision worse.

22. Thank You! The team would like to thank all who gave up their time to complete our surveys. 22