1 / 8

Tests For Multinomials

Tests For Multinomials. The Multinomial Situation. Have k qualitative choices Hypothesize: H 0 : p 1 , p 2 , … p k are the true proportions H 1 : At least one of these proportions is incorrect

kirkan
Download Presentation

Tests For Multinomials

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. Tests For Multinomials

  2. The Multinomial Situation Have k qualitative choices • Hypothesize: H0: p1, p2, … pk are the true proportions H1: At least one of these proportions is incorrect • Determine the expected number of observations for each choice if H0 were true: e1, e2 ,,, ek • e1 = np1; e2 = np2 …. ek = npk • All ei’s should be  5 for the 2 test to be valid • Observe the actual number of observations: f1, f2,…,fk

  3. The 2 Test • Determine the 2 statistic by 2 = ((fi-ei)2/ei) • If the2 statistic > 2, k-1 -- Accept H1 -- the proportions differ from the hyp. values • In EXCEL – • CHITEST(actual values, expected values) • gives the p-value for the 2 test

  4. Example • You hypothesize that of the cars driven by students to campus: • 26% are white, 16% are blue, 18% are red, 40% are some other color • Take a sample of 163 cars: • 46 white, 33 blue, 34 were red, 50 other • Can we conclude the true proportions are different from the hypothesized values?

  5. Set-Up columns for: Hypothesized Proportions Actual Observations Expected Observations

  6. SUM(D3:D6) Find the total # of observations

  7. =C3*$D$7 Drag down to E6 Find Expected # if hypothesized proportions are true.

  8. =CHITEST(D3:D6,E3:E6) Get p-value for the 2 test

More Related