PSY
07202 Statistics in Psychology
Assignment
15: SPSS Assignment 3
This
assignment is designed to give you practice choosing the appropriate test
statistic and calculating that test statistic using SPSS. You will get practice
running one-way and two-way ANOVAs along with correlations. You will need to
run the proper analysis to test each hypothesis, answer the questions,copy
your output under each question, and type the answers to the questions in
this file.
Please
submit the completed assignment to Assignment 15 labeled aslastname_Assignment15 as a .doc, .docx,
or .pdf file.
PART I: ANOVAs
For
this part, use the SPSS data set calledHSdata.sav
located in the Modules section. This data file contains 200 observations from a
sample of high school students with demographic information about the students
(gender, socio-economic status, ethnic background) as well as their scores on
standardized tests of reading, writing, mathematics, and social studies (you
used this data set for Assignment 11).
Study 1: You would like to see if there is a
significant difference in writing scores based on the student’s socio-economic
status. Test this hypothesis using the
data provided (make sure you do the appropriate post-hoc tests).
a. Proper test statistic:
b. Identify the independent variable:Socio-economic status
c. Identify the dependent variable:Writing
Scores
d. State null and alternative hypotheses:Ho= There is not a significant difference in writing scores based on
socio-economic status.
Hu= There is
a significant difference in writing scores based on socio-economic status.
Perform
the proper ANOVA using SPSS and copy and paste the output below. Make sure to select a post-hoc test, and
under Options, select Descriptives and Homogeneity Tests.
e. On the ANOVA table, circle or highlight the MSwithinand
MSbetweenand put them into an F ratio as if you were calculating it
by hand.
f. Is there a difference in writing scores between the different
socio-economic statuses? If yes, which
levels are different from each other based on the post hocs?
g. Write a sentence or two below describing the results of the
statistical testusing APA style.
Include any differences seen in the post hocs and all sample means and
standard deviations (for each of the groups). See Chapter 11 for APA
guidelines.
Study 2: You would like to
see if math scores are related to the type of program the student is in,
ethnicity, or an interaction between the two variables. Use the data provided to test this
hypothesis.
a. Proper test statistic:
b. Identify the independent variable(s):Type of program, ethnicity, or interaction.
c. Identify the dependent variable:Math
Scores
d. State the3 sets of null and alternative hypotheses (one for each
of your main effects and one for the interaction):
Ho= There is a significant relationship between math scores and the
program the student is in.
Ha= There is not a significant relationship between math scores and
the program the student is in.
Ho= There is a significant relationship between math scores and the
student’s ethnicity.
Ha= There is not a significant relationship between math scores and
the student’s ethnicity.
Ho= There is not a significant relationship between math scores and
the interactions between a student’s relationship or the type of group they are
in.
Ha= There is a significant relationship between math scores and the
interactions between a student’s relationship or the type of group they are in.
Perform
the proper ANOVA using SPSS and paste the output below. Follow the instructions in the ANOVA SPSS
PowerPoint for all of the options in the dialog box. For Plots, use ethnicity
on the horizontal axis, type of program as separate lines.
e. On the ANOVA table, circle the4 relevant MS values (one for
each main effect, one for the interaction, and one for the error term) and put
them into F ratios as if you were calculating your3 F ratios by hand.
f. In this type of analysis, if you have a significant interaction, you
should focus on that. Is your
interaction significant? Does this match
up with what you see in the plot?
g. Write a few sentences describing the results of the statistical test
using APA style. Make sure to create a table of your M & SD for each
of the groups (see Chapter 12 for APA guidelines).
PART II: CORRELATIONS
For
this part, you will be using the data file calledcars.sav, located in the Modules section. This data set contains
information about 406 different cars. It includes information about each car’s
miles per gallon, engine displacement, horsepower, weight, time to accelerate
to 60mph, year, origin, and the number of cylinders. Use this data file to
answer questions about the relationship between those variables. Make sure to
paste the SPSS output under each question.
1.
Run
correlations on the following variables:mpg,
engine, horse, weight.
a. What is the correlation (r value) between each of the different
relationships (hint: there should be 6 different relationships).
b. Which of these relationships are significant?
c. Write up 6 different sentences in APA style to report the results of
these relationships.
2.
Run
another correlation, this time usingmpg,
time to accelerate, and model year.
a. What is the correlation (r value) between each of the different
relationships (hint: there should be 3 different relationships).
b. Which of these relationships are significant?
c. Describe what the correlation betweenmpg and model year means in simple English. Does this
relationship make sense?
d. Describe what the correlation betweenmpg and time to accelerate means in simple English. Does this
relationship make sense?
3. Make a scatter plot of
the relationship betweentime to
accelerate and horsepower. Puthorsepower
on the X axis andaccelerate on
the Y axis.
a.
What is the
linear regression equation for this relationship?
b.
How much
time to accelerate would you predict in a car with 200 horsepower based on the
linear regression equation?
