PSYC 502 Final
January 13, 2011
AT THE END OF THE FINAL, YOU WILL NEED TO UPLOAD YOUR SYNTAX AND YOUR
OUTPUT TO THE “F:\COURSES\GRADS\PSYC502\Exam\Submit” FOLDER THAT WILL BE
AVAILABLE FOR YOU WHEN YOU DECLARE YOUR EXAM TO BE COMPLETE. YOU CAN
WRITE ON THAT LOCATION ONLY ONCE. PLEASE MAKE SURE THAT YOUR NAME IS ON
THE NAMES OF THE FILES THAT YOU UPLOAD.
1. The idea of “standard error” is central to all classical (parametric) statistics because it embodies the
following:
a. the idea of “randomness” of all of our estimates; and,
b. the idea that one can infer information about many from information about few.
Describe how the idea that underlies the concept of standard error helps us understand each one of
these two ideas. Please make sure that your discussion is conceptual rather than specific (i.e., your
response should not, to the extent possible, focus on formulas or calculations of confidence
intervals). (16 pts)
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ABOUT THE DATA THAT YOU WILL BE USING FOR QUESTIONS 2-5
The data are from a study of attitudes of KU students towards their education, career, and the KU. It was
conducted by a group of undergraduate students who were taking SOCI301 in Fall of 2005. The sample
was designed as a stratified random sample, representing students at each level of seniority. The survey
was administered in November. At the end of the semester, each record was matched with the registrar’s
records of SPA (Semester Point Average), so as to have the actual SPA (not self reports) on the data file.
2. The following are excerpts from a factor analysis output based on data from the student survey
described above. The data consist of 10 items, each rated on a 5-point scale, describing the level of
motivation of the students for coursework.
Please examine the output, and then describe how you would proceed to construct scale(s) that
measure the intended underlying construct (motivation). Please remember to interpret the meaning
of the scale(s) (10 pts).
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3. There is an ordinal motivation variable in the SPSS data provided to you (motivatn_o). There is also
an ordinal SPA variable in the data set (official_SPA). Use those two variable for the following
tasks:
a. Please design a table that shows the association of official_SPA with motivatn_o. Please
design and configure a table that can be included in a paper, reporting that association. Please
remember to include (1) a title for the table; (2) the layout of the table; (3) the contents of the
cells of the table; (4) labels for the rows and columns that are “publication quality”. (10 pts)
b. Please write a short paragraph that describes the data in the table you have created above.
Please take care to correctly select the numbers that you will use to comment on the table.
Conduct any additional statistical tests with these two variables as you see fit. (Carefully
selecting which numbers to cite, correctly referring to the numbers and percents, correctly
establishing the association or lack of association between the two variables, completeness
but no redundancy in the description of the data, fluency of English in writing, 10 pts)
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4. The following are specific directions for you to follow, in order to conduct a series of three
regression analyses.
a. The dependent variable is MOTIVATN, the level of motivation of the student for academic
work (the interval level measured version of the motivation variable that you worked with
above).
b. The independent variables for STEP 1 are: self esteem (selfest) of the student and the degree
to which the parents of the student were authoritarian (authpar_o, an ordinal variable with
just two categories).
c. STEP 2: A hypothesis that was postulated was as follows: the effects of authoritarian
parenting may partly depend on the self esteem of the student. In other words, the effects of
authoritarian parenting on student’s motivation may vary by the level of self esteem. Please
estimate a regression model that will test this moderation hypothesis. (10 pts)
d. STEP 3: In addition to the family background and personality factors such as the type of
parenting and self esteem, students’ plans for the future may influence their level of
motivation. We have two measures quantifying the nature of the students’ plans: (i) whether
the student has high career expectations (expcareer, an interval level variable) and (ii) the
clarity of the student’s career plans (clarity, an interval level variable). Please estimate a
regression model that will test this hypothesis.
e. Interpret the entirety of the analyses that you have conducted so far, including whether the
moderation hypothesis was supported, and if so, the interpretation of the way this moderation
operated. (24 pts)
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f. The regression analyses that you have conducted in a-e of Question 4 were conducted using
the REGRESSION command of SPSS. Now please replicate the analyses using the
UNIANOVA command. Please confirm that UNIANOVA provides the same results. Then,
please write below, at least one advantage of using REGRESSION rather than UNIANOVA,
and at least one advantage of using UNIANOVA rather than REGRESSION. (10 pts).
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5. Consider the regression analysis that you conducted in order to answer Question 4(d), the model that
was estimated in STEP 3. Please make of list of any of the regression assumptions that could have
been violated in that step. For each item on your list:
a. Please explain the assumption that was violated.
b. Please indicate the possible implication (impact, effect) of the violation of the assumption on
your inferences (conclusions). (10 pts)
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BONUS QUESTIONS
Please answer only ONE bonus question. Your bonus question assignment was given to you by NB at
the time of your individual consultation.
1. TABLES: The data for a table are given below. Please design a table that shows the association of
official_SPA with self esteem. Please design and configure a table that can be included in a paper,
reporting these data. Please remember to include (1) a title for the table; (2) the layout of the table
including the placement of row and column variables; (3) the contents of the cells of the table; (4)
labels for the rows and columns that are “publication quality”.
Please write a short paragraph that describes the data in the table you have created above. Please take
care to correctly select the numbers that you will use to comment on the table.
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2. REGRESSION ASSUMPTIONS:
In a regression model predicting satisfaction with the division of labor in the household (Y),
variables that were used were: the gender of the participant (X1); the education of the participant
(X2); education of the spouse of the participant (X3); and, whether there was any dependent children
in the household (X4).
a. A random sample of households was selected, and data were collected. The sample consisted
of all adult men and women living in each selected household. Please describe which
assumption of regression was violated by this study (sample) design? What may be the
implications? How may the problem be alleviated? What would be the implications of your
proposed solution to the problem? (7 pts)
b. Please describe how this regression model may have violated the assumption of
homoskedasticity? (3 pts)
3. SEM:
We have learned about (1) Standard Error of the Mean; (2) Standard Error of Prediction; (3) Standard
Error of Measurement, and (4) Standard Error of the Coefficient (regression).
a. Describe a common underlying idea for all of these “standard error”s and why this common
underlying idea is important in statistics.
b. What are the implications of the assumptions underlying the calculation of each one of these
standard errors for everyday applications of statistics? (10 pts)
4. FACTOR ANALYSIS:
In the data set that you worked with in questions 3-5 of this final exam, there was a series of 25
items that assessed the satisfaction of the students with the facilities, with the academic programs,
with social programs, with faculty, and with class schedules. The output of the factor analysis of
these 25 items is provided below. (1) How would you interpret each factor? (2) Please indicate if you
think this approach to the analyses of these 25 items was a sound (recommendable) approach. Write
a critique of this approach and propose an alternative if you decide that it was not the best approach
to construct one or more satisfaction scales. (10 pts)
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