Comments per User — CLT, Expectation, SD, and 95% CI
Context
You are measuring how many comments each user makes in a fixed time window (e.g., one week). Let X be the random variable "number of comments made by a randomly selected user in that window." You sample n users uniformly at random and record X1, X2, …, Xn.
Tasks
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Central Limit Theorem (CLT): Explain how it applies to the sample mean of comments per user.
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Expected Value: Define E[X] and explain how to compute/estimate the expected number of comments across all users.
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Population vs. Sample Standard Deviation: Differentiate σ (population) from s (sample) in this context.
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95% Confidence Interval: Construct a 95% CI for the mean number of comments.