Test Statistic (z) for 1 proportion: [ z = \frac\hatp - p_0\sqrt\fracp_0(1-p_0)n ] Where:
Test Statistic for 2 proportions: [ z = \frac(\hatp_1 - \hatp_2) - (p_1 - p_2)\sqrt\hatp(1-\hatp)\left(\frac1n_1 + \frac1n_2\right) ] Where ( \hatp = \fracx_1 + x_2n_1 + n_2 ) (pooled proportion) math tutor dvd statistics vol 7
If your professor speaks in monotone, uses a messy chalkboard, or rushes through Chapter 9 of your textbook (often titled "Hypothesis Tests for Proportions"), this DVD acts as your personal office hours. Test Statistic (z) for 1 proportion: [ z
This volume is not for everyone. Here is a breakdown of its ideal audience: Test Statistic for 2 proportions: [ z =
This is where the volume shines. Real-world statisticians rarely know the population standard deviation. Instead, they use the sample standard deviation (s) and the T-distribution.
Gibson dedicates a full lesson to the differences between the Z-table and the T-table. He explains: