Contingency Table

Question 1

How do you find the expected frequency in chi squared

Answer 1

E = Row Total x Column total /
Grand total

Question 2

How do you find error in chi squared

Answer 2

( Observed - Expected ) ^2/
Expected

Question 3

Assumptions of the chi squared test for association

Answer 3

Random sample displayed in a contingency table

Expected frequencies are atleast 5

Question 4

What do you write for H0 and H1 for chi squared for association test

Answer 4

H0: there is no association between

H1: there is an association between

Question 5

What do you write after, at the 5% level using for chi squared test for association

Answer 5

V = delete the last row and column and count how many cells are left

Question 6

How do you find the Test Stat for chi squared test for association

Answer 6

X^2 = { (Observed - Expected) ^2/
Expected
In formula book page 7

Question 7

What does critical region look like in chi squared test for association

Answer 7

Like Boltzmann distribution

Always upper tailed

Use table 6 right hand column only

Question 8

How to do the analysis for contingency table

Answer 8

Look at error table and identify the highest error
Look in the expected and observed tables
Say why you see and what it means

For example if there was a high error such as 32 and the expected was 89 while the observed was 143

You need to say the highest source of association is in the ( say what section the high score was in ) with an error of 32

There were more than expected, with 143 observed compared with 89 expected

Question 9

What if the expected frequencies are smaller than 5?

Answer 9

Combine rows/columns in an appropriate way to make the expected frequencies at least 5

Question 10

What is the disadvantages of combing the rows/columns to make the expected frequencies at least 5

Answer 10

You loose degrees of freedom, making it easier to find a significant result

If you combine too much and end up at 2x2 table and the Es are still too small, the sample itself is too small and the test cannot be tested done