Method to detect a gist change

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In a hospital the receptionist gives a letter to a patient. Waiting room of the general practitioner. Descriptions of image B. It is busy at the office. A woman gets an ...
Method to detect a gist change X.A.N.D.R.A. van Montfort, H.P. de Greef, D.G. Bouwhuis

Summary

The method applied

The Method !

A lot of changes in images and real-world situations can go undetected. It has been suggested that changes affecting the gist of an image are likely to be noticed. To test if a gist change facilitates change detection a method is developed to determine if a change affects the gist of an image. The gist is reflected in a verbal description of the interpretation of what an image is about. The method determines if a change in an image results in different interpretations of both versions of the image.

Step 1: Collecting descriptions, The Generator-task ! !

Generators provide descriptions One version per generator !

Descriptions of image A

Descriptions of image B

Waiting room of the general practitioner

Example of stimuli

A woman gets an invitation Two men see a beautiful woman and look at her

Thea with her broken leg gets redundancy pay

Develop a method to determine if a change in an image affects the gist Does the change affect the gist of the image?

!

18 sets of stimuli Two types of changes Intended to affect the gist Intended not to affect the gist 10 to 15 descriptions for each image Three raters

It is busy at the office

People at the office kindly converse with the w o m a n

Aim

!

Image A The original image

Getting fired

In a hospital the receptionist gives a letter to a patient

Image B A change intended to affect the gist of the image

Step 2: Categorizing descriptions, The Rater-task !

Waiting room of the general practitioner Thea with her broken leg gets redundancy pay

Introduction ! !

People at the office kindly converse with the woman In a hospital the receptionist gives a letter to a patient

Gist is a personal interpretation of what an image is about The perceived gist is reflected in a verbal description

!

A method is proposed to detect a gist change based on a "Generator-Rater" procedure A change affects the gist if the subjective interpretations of two versions of an image are systematically different

o Poor fit ü o Good fit o Poor fit ü o Good fit o Poor fit ü o Good fit o Poor fit ü

A woman gets an invitation

Getting fired

! o Good fit o Poor fit ü o Good fit o Poor fit ü o Good fit ü o Poor fit

!

o Good fit o Poor fit o Good fit o Poor fit o Good fit o Poor fit o Good fit o Poor fit

"Intended gist change" and "no gist change intended" analyzed separately Contingency tables analyzed for each rater separately Fitpattern 00 10 01 11

ü ü ü ü

!

!

Waiting room of the general practitioner

Thea with her broken leg gets redundancy In a hospital pay the receptionist gives a letter to a patient

A

B

Fit-pattern

Waiting room of the general practitioner Thea with her broken leg gets redundancy pay People at the office kindly converse with the woman In a hospital the receptionist gives a letter to a patient

1 1 1 1

0 0 1 0

10 10 11 10

Descriptions of image B It is busy at the office A woman gets an invitation Two men see a beautiful woman and look at her Getting fired

0 0 0 0

1 1 1 0

01 01 01 00

Rater 3 Source of descriptions image A image B 2 10 3 2 9

Image A vs Image B (intended gist change)

4

2

1

11

18

Image A vs Image C (no gist change intended)

17

-

1

-

18

Conclusions

Fit image

People at the office kindly converse with the woman

Rater 2 Source of descriptions image A image B 2 10 2 11 1

Gist change if 3 raters agree on significant difference (p