lecture12

lecture12 - Review of the 4-step program Statistical Power...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
± Review of the 4-step program ± Statistical Power ± Effect Size ± Introduction to the T-test 1. State the hypothesis 2. Set the decision criterion 3. Collect sample & compute statistic 4. Compare statistic to criterion and make a decision ± Are times to complete a 200 m sprint affected by cold temperatures? Assume that the population of 200 m sprint times has a 7 =22 s and ± =5. 1. State hypothesis ± H 0 : 7 =22 ± H 1 7 ± 22 2. Set Criterion ± ² =0.05, two-tailed ± Z critical =²1.96 3. Compute sample statistics ± A random sample of 25 runners ran in the cold and had a mean sprint time of M=25 s z = M ± ± ² M z = 25 ± 22 (5 25 ) = + 3 1 =+ 3.0 4. Make decision ± The obtained z of +3.0 is more extreme than our critical z, therefore reject H0 ± Cold temperatures increase times in the 200 m sprint.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
± The power of statistical test is the probably that the test will correct reject the null hypothesis ± Power = p(reject false H0) = 1-ß ± Why? ± Size of the treatment effect ± Alpha level ± 1-tailed vs. 2-tailed tests ± Sample size
Background image of page 2
± Need to know the sample mean (M), the population mean ( # ), and the population standard deviation ± ± Assumes ± does not change.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 9

lecture12 - Review of the 4-step program Statistical Power...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online