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Selection Bias

We carefully sampled the general population and found that most people are familiar with acquiescence bias.

Explanation

Blondie is giving a talk at the conference "Statistics Conference 2022." She asks for a show of hands from those attending the conference on whether they are familiar with selection bias. She uses this as part of her presentation, concluding that most people are therefore aware of what selection bias is.

Selection bias is when a survey or poll of some sort comes up with incorrect results due to those who were asked. For example, if you asked a group of people how many acres of land they own, your average number will be higher if you ask a group of farmers rather than a group of city residents.[citation needed]

The joke is that she is thus falling for the very thing she's trying to explain. A statistics conference is likely to have an audience consisting of professional statisticians, or at least people interested in the subject, and it is expected that most of them would thus be familiar with any mainstream statistical term, like selection bias. Had she asked a random sample of people in the street, many of them would likely not be sure what selection bias is. This effect is also the subject of 2357: Polls vs the Street.

This joke also ties into how statistics as a whole can be highly counter-intuitive and sometimes almost paradoxical, where things like the Monty Hall problem and survivorship bias lead people into thinking the answer to a problem is definitely in a place it's not. That Blondie, presumably a statistician herself, made this kind of (potentially deliberate) error is professionally embarrassing but not unprecedented.

The title text refers to Acquiescence bias, which is the tendency of people to respond positively to positive questions, for example, "Are you familiar with the famous webcomic xkcd ?" is more likely to generate the answer yes than "Are you familiar with that webcomic for engineers that nobody else understands until they go to Explain xkcd?" Acquiescence bias is not a widely known concept,[citation needed] making the results of this poll suspect; similar to the selection bias example above, the reason that the general public seems familiar with acquiescence bias may be because the surveyor themself fell victim to promoting acquiescence bias.