1 / 11

CHI SQUARE

CHI SQUARE. X ². “MATHEMATICAL JUDGE” OF PROBABILITIES X ² = ∑{(O-E)²/E} ∑= the sum of O= observed E= expected. Chi square is used to measure the significance of the data in comparison with what you expect to get. Chi square table. Problem #1.

kimberly
Download Presentation

CHI SQUARE

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. CHI SQUARE

  2. “MATHEMATICAL JUDGE” OF PROBABILITIES • X² =∑{(O-E)²/E} • ∑= the sum of • O= observed E= expected

  3. Chi square is used to measure the significance of the data in comparison with what you expect to get.

  4. Chi square table

  5. Problem #1 • F2= 5,474 yellow seeds & 1850 green seeds • 1. Find the total # of seeds • 2. What is the expected ratio? • 3. How may yellow and green seeds would you expect? Yellow________,green____

  6. 4. For yellow seeds, used the formula • (O-E)²/E. Yellow ________ • 5. For green seeds , use above formula. green _______ 6. Add the #’s together.

  7. Did you get? • 0.263 • Yea!!!!!!!!!!!!!!!!!

  8. 7. Compare your chi square valve to the Chi square table.

  9. With one degree of freedom we could be allowed a chi square as large as 3.84 and the results would still be considered significant to 5%. X² = 0.263 there’s less than a 5% chance this 3:1 happened by accident.

  10. The degrees of freedom are one less than the number of categories you have to work with. We have two categories, yellow and green, so we have one degree of freedom.

  11. Find the chi square for the C-fern. • Use the class totals. • The p= cc X Cc • cc= polka dot and is recessive • Cc = wild type and heterozygous • What would the expected ratio for F1 be with this cross?

More Related