Chpt 12 review

Question 1

What does x2 test statistic used for

Answer 1

1. test for equality, 2. test for independence, 3. Goodness of fit test

Question 2

The test for Equality, what is the Null and Alternative hypothesis

Answer 2

HO: P1=P2=P3

Question 3

When you reject HO for Equality test, what can you conclude

Answer 3

not all pop proportion are equal

Question 4

What is the degrees of freedom for test of equality

Answer 4

df = k-1

Question 5

If we reject Ho for an equality test, what can you do

Answer 5

you can determine where the differences exists by using Marasculio procedure

Question 6

In the Marasculio procedure, what are the steps and formulas

Answer 6

1. Phat 1 (do for all pops) oberved/column total
2. Compare Phat 1 - Phat 2 (etc for all pops)
3. Calculate CV for each
   a. calculate the x 2 for a = 0.05 (for example)

• use k-1 degrees of freedom
  then calcualte the rest of the equation (provided on exam)

4. Compare Phat 1 - Phat 2 etc to the CV
5. if Phat 1- Phat 2 is greater than CV12 then it is significant and therefore conclude the difference is in there

Question 7

What is the null hypothesis for the test for independence

Answer 7

HO: Beer pref is independent of gender
Ha: Beer pref is not independent of gender

Question 8

What type of variables are the test for independence

Answer 8

categorical variables

Question 9

What are the degrees of freedom for the test of independence

Answer 9

df (rows-1)(columns -1)

Question 10

What can you use the goodness of fit test for

Answer 10

1. change in pop proportion

2. normal distribution

Question 11

What is the null hypothesis for a goodness of fit test for change in pop proportion

Answer 11

Ho: PA=.30 PB=.50 PC=.2

Question 12

What type of test is the change in pop proportion

Answer 12

multinomial (more than 2) it is an extension of the binomial

Question 13

What is the degrees of freedom for chang ein pop porporiton

Answer 13

k-1

Question 14

if you reject the null hypothesis H0 for the change in pop proportion, what can be said

Answer 14

it is significant, there has been a change in pop proportion

Question 15

What is the formula for calculating the normal distribution

Answer 15

do from sheet

Question 16

If you get a question regarding a uniform distribution, what is the degrees of freedom

Answer 16

k-1

Question 17

with a uniform calculation, how do you calculate the expected number

Answer 17

find the mean of all the observed numbers - this is the expected for each

Question 18

if you reject Ho in a uniform distribution (ie mon, tues, wed, thurs ….) what can you say

Answer 18

significant, not uniform

Question 19

Marascuillo procedures is used for

Answer 19

testing the equality of 3 or more pop proportions

Question 20

In a normal distribution with 30 observations what would the expected number be

Answer 20

30/5 = 6
6 is the intervals
5 is the EXPECTED Number

Question 21

what is the degrees of freedom for a normal distribution

Answer 21

k-p-1

k - number of observations
p - 2 for mean and sd

Question 22

Using the Marascuillo procedure, when comparing phat 1 - phat 2 to cv12 what is significant

Answer 22

When p hat1 - phat2 > CV

Significant and this one is different