1 / 13

Happiness comes not from material wealth but less desire.

Happiness comes not from material wealth but less desire. Inferences Comparing Two Population Means. Paired samples Independent samples Estimation Tests- z test and t test. Paired Samples.

chapa
Download Presentation

Happiness comes not from material wealth but less desire.

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Happiness comes not from material wealth but less desire.

  2. Inferences Comparing Two Population Means Paired samples Independent samples Estimation Tests- z test and t test

  3. Paired Samples • If the same set of sources are used to obtain data representing two populations, the two samples are called paired. The data might be paired: • As a result of the data from certain “before” and “after” studies • From matching two subjects to form “matched pairs”

  4. Tests for Paired Samples • Calculate the pair differences • Proceed as in one sample case Example: Figure 11.1

  5. Independent Samples • The two samples are unrelated • Example: Chapter 11, problem 15 (heart.mpj)

  6. Estimation for m1-m2 • Point estimator • Confidence interval • Normal populations with known s1,s2, or two large samples (n1,n2>30): Z interval • Normal populations with unknown s1,s2: t interval • s1=s2: pooled t interval • s1=s2: approximate t interval • At least one nonnormal population and at least one small sample: out of our scope

  7. Two Populations

  8. Tests for m1-m2 = d0 • Normal populations with known s1,s2, or two large samples (n1,n2>30): Z test • Normal populations with unknown s1,s2: t test • s1=s2: pooled t test • s1=s2: approximate t test • At least one nonnormal population and at least one small sample: out of our scope

  9. Two Populations

  10. Minitab: stat>>basic statistics>>2 sample t …

  11. Results for: HEART.MTW • Two-Sample T-Test and CI: pdi, trtment • Two-sample T for pdi • trtment N Mean StDev SE Mean • 0 73 91.9 16.5 1.9 • 1 70 97.8 14.7 1.8 • Difference = mu (0) - mu (1) • Estimate for difference: -5.85 • 95% CI for difference: (-11.02, -0.68) • T-Test of difference = 0 (vs not =): T-Value = -2.24 P-Value = 0.027 DF = 141 • Both use Pooled StDev = 15.6318 • Two-Sample T-Test and CI: pdi, trtment • Two-sample T for pdi • trtment N Mean StDev SE Mean • 0 73 91.9 16.5 1.9 • 1 70 97.8 14.7 1.8 • Difference = mu (0) - mu (1) • Estimate for difference: -5.85 • 95% CI for difference: (-11.01, -0.70) • T-Test of difference = 0 (vs not =): T-Value = -2.24 P-Value = 0.026 DF = 140

More Related