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## AP®︎/College Statistics

### Course: AP®︎/College Statistics>Unit 10

Lesson 5: Carrying out a test for a population proportion

# Calculating a z statistic in a test about a proportion

Calculating a z statistic in a one-sample z test about a proportion.

## Want to join the conversation?

• It was never explained why z is the correct test statistic for this significance test. I imagine it isn't always the "correct test statistic" and would have appreciated an explanation of what the other choices would be and why. And if it is indeed the only one, then why is that. It would go a long way as to understanding why he did what he did here.

Thank you.

ETA: I googled test statistic and found there are 4 main ones, Z-test, T-test, ANOVA and Chi-Square Test. I didn't realize these were how the test statistic were used/found. • Duno why he stopped in the middle. This is the most important video to explain the significance test in action • Shouldn't we be taking the standard deviation of the actual distribution rather than the standard deviation of the sample distribution?

Are we assuming they are approximately the same?   