University of Phoenix Material

Time to Practice â Week Four

Complete Parts A, B, and C below.

Part A

Some questions in Part A

require that you access data fromStatistics for People Who (ThinkThey) Hate Statistics.This data is available on the student website

under the Student Text Resources link.

1. Using the data in the file named Ch. 11 Data Set 2,

test the research hypothesis at the .05 level of significance that boys raise

their hands in class more often than girls. Do this practice problem by hand

using a calculator. What is your conclusion regarding the research hypothesis?

Remember to first decide whether this is a one- or two-tailed test.

2. Using the same data set (Ch. 11 Data Set 2), test

the research hypothesis at the .01 level of significance that there is a

difference between boys and girls in the number of times they raise their hands

in class. Do this practice problem by hand using a calculator. What is your

conclusion regarding the research hypothesis? You used the same data for this

problem as for Question 1, but you have a different hypothesis (one is

directional and the other is nondirectional). How do the results differ and

why?

3. Practice the following problems by hand just to see

if you can get the numbers right. Using the following information, calculate

the t test statistic.

a.

14X1 = 62 X2 = 60 n1 = 10 n2 = 10 s12= 6 s22= 10″>

b.

14X1 = 158 X2 = 157.4 n1 = 22 n2 = 26 s12= 4.23 s22= 6.73″>

c.

14X1 = 200 X2 = 198 n1 = 17 n2 = 17 s12= 6 s22= 5.5″>

4. Using the results you got from Question 3 and a

level of significance at .05, what are the two-tailed critical values

associated with each? Would the null hypothesis be rejected?

5. Using the data in the file named Ch. 11 Data Set 3,

test the null hypothesis that urban and rural residents both have the same

attitude toward gun control. Use IBMÂ® SPSSÂ®software to

complete the analysis for this problem.

6. A public health researcher tested the hypothesis

that providing new car buyers with child safety seats will also act as an

incentive for parents to take other measures to protect their children (such as

driving more safely, child-proofing the home, and so on). Dr. L counted all the

occurrences of safe behaviors in the cars and homes of the parents who accepted

the seats versus those who did not. The findings: a significant difference at

the .013 level. Another researcher did exactly the same study; everything was

the sameâsame type of sample, same outcome measures, same car seats, and so on.

Dr. Râs results were marginally significant (recall Ch. 9) at the .051 level. Which

result do you trust more and why?

7. In the following examples, indicate whether you

would perform a t test of independent

means or dependent means.

a. Two groups were exposed to different treatment levels

for ankle sprains. Which treatment was most effective?

b. A researcher in nursing wanted to know if the

recovery of patients was quicker when some received additional in-home care

whereas when others received the standard amount.

c. A group of adolescent boys was offered

interpersonal skills counseling and then tested in September and May to see if

there was any impact on family harmony.

d. One group of adult men was given instructions in

reducing their high blood pressure whereas another was not given any

instructions.

e. One group of men was provided access to an exercise

program and tested two times over a 6-month period for heart health.

8. For Ch. 12 Data Set 3, compute the t value and write a conclusion on whether

there is a difference in satisfaction level in a group of familiesâ use of

service centers following a social service intervention on a scale from 1 to

15. Do this exercise using IBMÂ®SPSSÂ®software, and report

the exact probability of the outcome.

9. Do this exercise by hand. A famous brand-name

manufacturer wants to know whether people prefer Nibbles or Wribbles. They

sample each type of cracker and indicate their like or dislike on a scale from

1 to 10. Which do they like the most?

Nibbles rating

Wribbles rating

9

4

3

7

1

6

6

8

5

7

7

7

8

8

3

6

10

7

3

8

5

9

2

8

9

7

6

3

2

6

5

7

8

6

1

5

6

5

3

6

10. Using the following table, provide three examples

of a simple one-way ANOVA, two examples of a two-factor ANOVA, and one example

of a three-factor ANOVA. Complete the table for the missing examples. Identify

the grouping and the test variable.

Design

Grouping variable(s)

Test variable

Simple ANOVA

Four levels of hours of

trainingâ2, 4, 6, and 8 hours

Typing accuracy

Enter Your Example Here

Enter Your Example Here

Enter Your Example Here

Enter Your Example Here

Enter Your Example Here

Enter Your Example Here

Two-factor ANOVA

Two levels of training

and gender (two-way design)

Typing accuracy

Enter Your Example Here

Enter Your Example Here

Enter Your Example Here

Enter Your Example Here

Three-factor ANOVA

Two levels of training,

two of gender, and three of income

Voting attitudes

Enter Your Example Here

Enter Your Example Here

11. Using the data in Ch. 13 Data Set 2 and the IBMÂ®

SPSSÂ®software, compute the F ratio for a comparison between the three levels representing the

average amount of time that swimmers practice weekly (< 15, 15â25, and > 25

hours) with the outcome variable being their time for the 100-yard freestyle. Does

practice time make a difference? Use the Options feature to obtain the means for

the groups.

12. When would you use a factorial ANOVA rather than a

simple ANOVA to test the significance of the difference between the averages of

two or more groups?

13. Create a drawing or plan for a 2 Ã 3 experimental

design that would lend itself to a factorial ANOVA. Identify the independent

and dependent variables.

From Salkind (2011). Copyright Â© 2012

SAGE. All Rights Reserved. Adapted with permission.

PartB

Some questions

in Part B require that you access data fromUsing SPSS for Windows and

Macintosh. This data is available on the student website under the

Student Text Resources link.

The data for Exercise

14 is in the

data file named Lesson 22 Exercise File 1.

14. John is interested in determining if a new teaching

method, the involvement technique, is effective in teaching algebra to first

graders. John randomly samples six first graders from all first graders within

the Lawrence City School System and individually teaches them algebra with the

new method. Next, the pupils complete an eight-item algebra test. Each item

describes a problem and presents four possible answers to the problem. The

scores on each item are 1 or 0, where 1 indicates a correct response and 0

indicates a wrong response. The IBMÂ®SPSSÂ® data file

contains six cases, each with eight item scores for the algebra test.

Conduct a one-sample t test on

the total scores. On the output, identify the following:

a. Mean algebra score

b. T test value

c. P value

The data for Exercise

15 is in thedata

file named Lesson 25 Exercise File 1.

15. Marvin is interested in whether blonds, brunets,

and redheads differ with respect to their extrovertedness. He randomly samples

18 men from his local college campus: six blonds, six brunets, and six

redheads. He then administers a measure of social extroversion to each

individual.

Conduct a one-way ANOVA to investigate the relationship between hair

color and social extroversion. Conduct appropriate post hoc tests. On the

output, identify the following:

a. F ratio for the group effect

b. Sums of squares for the hair color effect

c. Mean for redheads

d. P value for the hair color effect

From Green & Salkind

(2011). Copyright Â© 2012 Pearson Education. All Rights Reserved. Adapted with

permission.

PartC

Complete the questions below. Be specific and provide examples when relevant.

Cite any sources consistent

with APA guidelines.

Question

Answer

What is meant by independent samples?

Provide a research example of two independent samples.

When is it appropriate to use a t test for dependent samples? What is

the key piece of information you must know in order to decide?

When is it appropriate to use an ANOVA?

What is the key piece of information you must know in order to decide?

Why would you want to do an ANOVA when

you have more than two groups, rather than just comparing each pair of means

with a t test?

## About The Author: Admin

More posts by admin