Standard Deviation-The standard deviation is a measure of variability in a sample-It tells us, “on average…how far are people from the mean”-It’s easier to do standard deviation by making a table first Sampling Distribution-Sampling distribution has 2 important propterties that we want to remember 1. It has a mean that is equal to the population mean 2. It has a standard deviation that is equal to the population standard deviation Confidence Interval-Now that we know how to calculate the SD, lets calculate a confidence interval for the avg. in the distribution-We know…the mean of the sample means from repeated large samples, is the population avg. (CLT)-If I repeatedly sample 100 IU students and ask about GPA’s, the mean of the sample means (i.e. average of GPA sample averages) is equal to the average population-Under ordinary circumstances, we are not able to repeatedly sample a population. This is where we use confidence intervals.-To calculate the CI, we first estimate the
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This note was uploaded on 11/10/2011 for the course SOC 110 taught by Professor Latouche during the Fall '11 term at Indiana.