What are z-scores? A z-score measures exactly how many standard deviations above or below the mean a data point is.

A z-score is an example of a standardized score. A z-score measures how many standard deviations a data point is from the mean in a distribution.

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Find the z-score of a particular measurement given the mean and standard deviation.

In any normal distribution, we can find the z-score that corresponds to some percentile rank. If we're given a particular normal distribution with some mean and standard deviation, we can use that z …

Qualitative sense of normal distributions Normal distribution problems: Empirical rule Standard normal distribution and the empirical rule (from ck12.org) More empirical rule and z-score practice (from …

The 3% on each side of the distribution ensures that the confidence interval is centered around the mean. After calculating the z-score for 97% probability, you would indeed subtract 3% from each tail …

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In a significance test about a population proportion, we first calculate a test statistic based on our sample results. We then calculate a p-value based on that test statistic using a normal distribution.

Why do we calculate the probability of getting our result OR HIGHER? I know this varies depending on whether you want to test if a population value is greater or smaller or just different than expected. But …