Description of SOC Images Variation amongst SOCOs

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Description of SOC Images Variation amongst
SOCOs?

• Chris Handy, Mariam Tariq
• Khurshid Ahmad

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Variation amongst SOCOs?

• Are SOCOs always consistent?
• How does this affect retrieval?

• 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 SOCOs about
  individual images.

• A consistency of description will help in
  automatically indexing the images for later
  retrieval.

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Variation amongst SOCOs?

• Are SOCOs always consistent?
• How does this affect retrieval?

• A consistency of description may be in the
  description of objects as well as the location of
  the objects.
• Description of an object, for us, includes,
  identification and further elaboration.

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Variation amongst SOCOs?

• We analysed a set of images of a crime scene
  described by 8 different SOCOs.
• SOCOs typically identify, locate, and give
  additional information in 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.

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Variation amongst SOCOs?
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Variation amongst SOCOs?
Identification Step 1
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Variation amongst SOCOs?
Identification Step 2
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Variation amongst SOCOs?
Location
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Variation amongst SOCOs?
Additional Information
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Variation amongst SOCOs?
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Variation amongst SOCOs?
Identification Step 1
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Variation amongst SOCOs?
Identification Step 2
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Variation amongst SOCOs?
Location
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Variation amongst SOCOs?
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 corner of
Dempsey Place. Entirety view front of church
with Dempsey Road on right hand side as viewed
from the front of the church.
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Variation in vocabulary

• Data was tabulated to evaluate variation/consisten
  cy

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Observations (1)

• Several observations made about the data in
  general.

• 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

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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.

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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.

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Conclusions (1) -Variation

• There is evidence of indexer variation at the
  lexical level

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Conclusions (2) -Variation

• However at the conceptual level there is more
  consistency

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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.

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Thank You!

• The team would like to thank all who gave up
  their time to complete our surveys.

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