|1. Is the sample representative of the Population ?|
|- Is the
- Is the sample biased?
Statistical bias is broader than personal bias.
A very common bias is "nonresponse bias."
|2. Is the sample large enough?|
|Sample Size for Forecasting a Close Election|
|3. Do the questions tempt respondents toward biased ansuers?|
|4. What is the agenda of the people collecting and presenting the data?|
|5. Do the respondents know the answers to the questions?|
|6. Is there a standard to compare the results against?|
|-Weakness of before-and-after|
|7. What are the alternative explanations for the results?|
|8. Is there a statistical "lie" in the presentation of the results?|
|Note on How to Lie with Statistics|