Assignment7ChiSquareWorksheet.docx

PSY 305 Assignment 7

Assignment 7

· Round each decimal answer to two digits or you will get incorrect results on your work and your will get no points in D2L. Only the precise answer obtained after rounding to the two decimal places will be correct.

The following is data from a drug study to see if animals survived better receiving a drug compared to those that did not.

Ho: The survival of the animals is independent of drug treatment.

Ha: The survival of the animals is associated with drug treatment

Complete the row & column totals in the following contingency table and calculate the expected values and fill in the blank for that follow.

 Dead

 Alive

Total

 Treated

 36 (___6) Cell A

 14 (___7)Cell B

 _____3

 Not treated

 30 (___8)Cell C

 25 (___9) Cell D

_____4

 Total

_______1

______2

_____5

Remember that,

Expected value for Cell A = (Row Total item 3) x (Column Total item 1)/Grand Total (item 5)

Expected value for Cell B = (Row Total item 3) x (Column Total item 2)/Grand Total (item 5) 18.53

Expected value for Cell C = (Row Total item 4) x (Column Total item 1)/Grand Total (item 5) 34.57

Expected value for Cell D = (Row Total item 4) x (Column Total item 2)/Grand Total (item 5)

20.43

10. The X2 for this study is 3.418. What is its df? ____

11. What is the critical value for a X2 with this df at the .05 level? (Table C-7)________

12. Based on this information did we find support for the claim that the survival of the animals

depends on the drug treatment?

A. Yes

B. No