Ch4 - Estimating with Uncertainty

What is the sampling distribution?

The probability distribution of an estimate based on all possible samples of a given size from a population.

Define sampling error (of the mean) and give the formula for true standard error.

standard error = a measure of the statistical accuracy (predicts sampling error) of an estimate.

Give the formula for the estimate of the standard error of the mean

This gives use the difference between our sample mean and the true population mean.

What does the confidence interval (CI) tell us?

The CI tells use that values that fall within the interval are plausible (by a specified probability) in terms of being a parameter.

→ 95% CI for the mean = “Y-bar” ± 2SE (max/min of CI)

→ when talking about CIs make sure you don’t suggest the parameter is changing.

What is pseudoreplication?

It is an error that appears when samples are not independent, but they are treated as though they are (samples to same seal twice).

→ to acknowledge that there’s been repeated sampling you have to find the mean so you end up with one measurement for each sample.