Exercise 2: Why Squire's Reanalysis Changes the Real Lesson — Possible Solution
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The popular version of the Literary Digest story teaches a single,
simple lesson: a bad sample frame (skewing toward wealthy phone/car
owners) explains the whole failure, so the fix is simply "sample from
a source that represents the whole population." Squire's 1988
reanalysis complicates that in a genuinely important way: even
correcting for the skewed sample frame, the poll would still have
predicted Roosevelt correctly if response rates had been equal across
supporters of both candidates. The dominant real cause was actually
non-response bias - Landon supporters were simply more likely to mail
their ballot back.

This changes the practical lesson a researcher should take away. The
popular version implies the fix lives entirely at the sampling-design
stage - pick better initial recipients. Squire's reanalysis shows a
second, separate failure point exists even in a well-designed sample:
who chooses to actually respond can itself introduce bias, completely
independent of who was initially selected. A researcher who only fixes
the sample frame, but ignores differential response rates between
groups, could still end up with a badly biased result.

This is exactly the kind of "popular story vs. more complicated real
reanalysis" correction the course has applied elsewhere - the original
story isn't wrong, but treating it as the complete explanation would
lead to fixing only half of the real problem.

ANSWER: Squire's reanalysis matters because it identifies a second,
separate source of bias (differential non-response between supporter
groups) that the popular sample-frame-skew story leaves out entirely.
The practical lesson changes from "just sample from a better source"
to "also watch for who actually chooses to respond, since even a
well-chosen sample can still be biased by unequal response rates."

WHY THIS WORKS AS AN ANSWER
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This explains specifically how the added nuance changes the practical
takeaway a researcher should apply, rather than just restating that
Squire's reanalysis exists.