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Equation 20 · Part 6 · Forty Million Clicks Through One Uneven Door

fraction

CSDBc(δ)=δσYfc1−fc.\mathrm{CSDB}_c(\delta) = \frac{\delta}{\sigma_Y}\sqrt{\frac{f_c}{1-f_c}} .
fraction

What this part means

Divide the expression above the line by the one below it.

Its job in the formula

The expression above the fraction bar is divided by the complete expression below it. The denominator must not be zero.

The passage around this formula

Solving for the minimum defect correlation needed to produce a given bias δ\delta , and taking the most generous possible bound for a roughly binary preference indicator, σY\sigma_Y ≤\le 0.5 , gives what this article calls, for a specific country c , its Country Selection-Divergence Bound: CSDBc(δ)=δσYfc1−fc\mathrm{CSDB}_c(\delta) = \frac{\delta}{\sigma_Y}\sqrt{\frac{f_c}{1-f_c}} . This is a DERIVED quantity, not a measurement: it has not been run against real per-country population totals or the actual SharedResponsesSurvey.csv microdata, and no value of ρR,Y\rho_{R,Y} for any real country is claimed here. What can be computed honestly, using only the paper’s own reported extremes for n — 101 respondents at the low end, 448,125 at the high end [ 1 ] — is how small…

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Learn the underlying idea

A fraction a/b means a divided by b. The top number is the numerator; the bottom number is the denominator, and it cannot be zero.

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Sources cited in the surrounding passage

These citations provide research context; check each source for the exact claim it supports.