Statistics: Ch 7 Sample Variability (2 of 14) Two Useful Distributions of a Sample

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We will learn the sample size (n) must be large enough to represent a population:
1) when many samples (each size n) are taken “the (sample) distribution of the sample means” tends to be a normal distribution,
2) when many samples (each size n) are taken “the (sample distribution of the sample ranges” tends to be skewed to the right.

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[DennisDavisEdu]

Professor, your second graph (right-skewed graph of the sample range distributions) struck me as an excellent illustration of why sample variances are biased and require the (n-1) denominator as a correcting factor. Sample means tend to reflect the population mean (unbiased), but sample variability tends to under-reflect population variability (biased). Wonderful!

[elle]

thank you professor for your hard work! you are a great person and you've impacted so many people's lives! huge respect :)

[TheSpyFardin]

Sir it really seems like that you're 8 years less old than now due to putting that flag beside you!!!
Because you used to put that flag in the earliest time of this channel!!