Final answer:
The assertion that inconsistent responses to the same questionnaire over time automatically make the questionnaire invalid is false. Changes in responses can be due to factors like response bias or the subjective nature of questions, affecting reliability but not necessarily validity.
Step-by-step explanation:
If the same questionnaire about income and education is given to the same person at two different times, and nothing significant has changed between the two times, the expectation is that the responses should be the same. If they are not, one might initially think that the questionnaire could be described as invalid. However, this is false. Inconsistencies in responses can be due to a variety of factors, including but not limited to, response bias or the participant's current mood and context, rather than the validity of the questionnaire itself. Validity refers to how well a test measures what it is purported to measure.
Response bias and factors such as question wording, interviewer bias, and the subjectivity in open-ended questions can lead to different answers. Qualitative data that represents subjective views or opinions may vary based on a myriad of reasons. Reliability refers to the consistency of a measure, which might be what is called into question if answers differ, but does not necessarily imply invalidity.
Furthermore, the repetition of an experiment or survey, similar to administering a questionnaire multiple times, can help establish the reliability of the results, rather than their validity. Therefore, a difference in responses does not automatically constitute a validity issue but rather could be an issue of reliability or simply the nature of the survey questions and the context in which they are answered.