Conclusion about parking situation of Minnesota vikings games?

Question

The first 100 people go to a Minnesota Vikings game and of the 60,000 who attended game are given a survey asking them to evaluate the parking situation at the game is this a valid survey to reach any conclusion about the parking situation and Minnesota Vikings game

Answer 1

Horribly worded queston...

Perhaps you mean to say: The first 100 of the 60,000 people attending a Vikings game were asked to complete a survey about the parking situation, is that a valid survey?

You can't say for certain that it is a valid survey without actually knowing the survey questions, but you can still so it is not. And that's what I believe it is for two reasons:

1. If you sample a population, you really want to have a randomized sample. In other words, 100 randomly chosen people out of 60,000 attending were asked to complete a survey, it could be a statistically valid survey. But the first 100, or the last 500, or the middle 75, are not random. Specific to this situation, the first 100 probably all got a great spot in exactly the lot they wanted. But that's only if they actually used the parking facilities. Which brings up the second issue.

2. Of the people asked to comment on the parking, how many actually used the parking facilities? If half always took the train, bus, or Uber, their only knowledge of the parking situation would be what someone else told them. What's the validity of a survey who's first question is "Did you use the parking?" and 50 out of 100 said no?

Answer 2

A survey is valid if it measures what it purports to measure. The problem does not really make explicit what the survey was meant to measure.