1. Training course on developing and using questionnaires for agricultural surveys
Field Testing
Post evaluation methods
Marco Ballin
Istanbul, July 2011

2. Post evaluation methods
These methods look to evaluate indirectly the quality of the questionnaire during or after the real data collection
Under this item cab be classified most of the methods used to evaluate the quality of the surveys
Most of times the results can be used to improve next editions of the same survey
Istanbul, July 2011 2

3. Post evaluation methods
Main post-evaluation methods are the following:
Analysis of item non response data
Analysis of response distributions
Analysis of editing and imputation phase
Reinterview studies
Istanbul, July 2011 3

4. Analysis of item non response data
Post evaluation methods
Analysis of item non response data
Item non response occurs when a respondent provides some, but not all, of the requested information
The analysis should start by investigating the extend of item non response
Questions with higher non response have tove deeply analysed.
It could be important to identify the position of the question in the questionnaire or the profile of respondent
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5. Analysis of response distribution
Post evaluation methods
Analysis of response distribution
This analysis can help in finding out problems of the categories used for closed questions, outliers.
It helps to compare different version of the same question
Istanbul, July 2011 5

6. Analysis of editing and imputation phase
Post evaluation methods
Analysis of editing and imputation phase
This analysis can help in finding out the question where inconsistencies or invalid data can be found
Numerous edit failures may indicate problems with wording, definitions, instructions, etc.
Istanbul, July 2011 6

7. Reinterview studies Post evaluation methods
These surveys are mainly aimed at estimating the measurement error arising from the method of data collection, the respondent or the questionnaire
There are two main approaches:
To carry out the new interview in the same conditions of the first one (mainly used to estimate the simple response variance)
To carry out a more accurate interview on a sub sample of respondent to the survey (mainly used to estimate the systematic component of the response error)
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8. Post evaluation methods
Discussion
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