Equation 33 · Part 1 · Forty Million Clicks Through One Uneven Door
Symbol sigma_Y
What this part means
the outcome’s population standard deviation.
Its job in the formula
sigm is part of the quantity the equation computes from the expression on the right.
Full expression→Symbol sigma_Y→Article meaning
Where the article explains it
For a population of size N with a binary response indicator R (did this person’s data reach the sample) and an outcome Y (their realized value on some Moral-Machine-relevant preference indicator), Meng’s identity relates the sample mean to the true population mean as - = \, , where is the “data defect correlation” between selection and outcome across the full population, f = n/N is the sampling fraction, and is the outcome’s population standard deviation.
The passage around this formula
…as the clusters differ, the paper’s own demonstration that observed demographics barely move the estimates does not bound the unobserved selection process nearly as tightly as it appears to. Using a more conservative = 0.3 , reflecting that most individual preference indicators are not split near 50/50, raises both bounds by roughly two-thirds — to about 0.003 and 0.013 — without changing the conclusion that the required leak is tiny.
Learn the underlying idea
A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.
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Sources cited in the surrounding passage
These citations provide research context; check each source for the exact claim it supports.