Course Description: The course offers a general
introduction to psychometric methods primarily emphasizing classical
test theory, test construction and validation, and test use. The
emphasis lies with developing a firm understanding of basic
psychometric concepts. This course lays a foundation for more
advanced courses in specific topics introduced here. The course
understands psychometircs and testing as applying broadly, not just to
paper and pencil tests but also to performance assessments, behavioral
observations, measured variables in experiments and quasiexperiments,
surveys, and other forms of behavioral data collection. However, much
of the material will emphasise measurement involving multiple
indicators of a common construct.
Course Objectives: The
course assumes a foundation in basic statistics and a healthy curiosity
but little more. The more you put into the course, the more you will
get out of the course. The course design relfects the following
objectives.
1. Students will gain a basic understanding of the foundations of
test theory that will prepare them to pursue more advanced topics
(e.g., item response theory, structural equation modeling).
2. Students will gain the background and confidence to critically
read technical manuals and other documentation in conjuction with use
of published tests.
3. Students will gain facility with conceptual tools for thinking
through issues of validity and reliability as applied to all measures
from dependent variables in experiments to large scale testing programs.
4. Students will gain a level of comfort with algebraic
representations of test scores and the use of these to think through
applied problems related to test use and interpretation.
5. Students will gain an increased sensitivity to the fallibility
of educational and psychological tests and the limits to their use and
interpretation.
6. Students will gain exposure to the use of statistical software
for conducting psychometric analyses and some experience with such
analyses.
7. Those students who choose to avail themselves of it will optionally
leave the course with additional experience using various software
packages for psychometric data analysis.
I will illustrate
psychometric concepts using a variety of software packages.
Familiarity with the software is not a course requirement.
However, learning psychometrics simply by reading about it is akin to
learning to swim, ski, or play a musical instrument simply by reading
about it. Actual practice is a much more effective method. Whether you
use a simple calculator, a spreadsheet, or advanced statistical
software, it is a good habit to play around with the material by
constructing concrete examples and taking a tryandsee attitude toward
the material. If something seems puzzling, make up an example and try
it out. If something seems counterintuitive to you, try to
construct a counterexample. The more concrete you make psychometrics,
the more comfortable you will feel with the material, the better you
will understand it, and the more skills you will develop that you can
apply outside of the class. None of the this is required for the
course, but it will make it more fun, more interesting, and more
practical.
Examinations: The examinations will
not be cumulative but
later material will always presuppose a familiarity with prior
material.
You are allowed one twosided 8.5 x 11 inch handwritten page of notes
and a
calculator
to be used during each examination. Examinations will emphasize
your
ability to reason using psychometric principles studied in the
course. Although examinations will not emphasize computations,
they will require some computation. Exercises in the text book
offer the best test preparation.
Homework: Come prepared to turn in
homework assignments
at the beginning
of class. Given that the homework comes due before the
corresponding lecture (and the fact that you can look up the answers if
you get stuck), I will grade more on completeness than accuracy.
The assignments primarily serve the purpose of allowing you to test
your understanding of the reading before the lecture and thus better
recognize where you have questions about the material.
Course Project:
Write a proposal for the validation of a test of your construction
following the format below. Double space the proposal and use APA
format and style. However, printing on both sides of the page is
allowed to save paper.
A. Title page including your name and affiliation.
B. Abstract (180 words max).
C. Purpose of the test (250 words max). Describe the intended use of
the test. Describe the intended users and the intended test taking
population. Explain what the test would contribute over and above
existing tests. Describe the theoretical rationale behind the test.
D. Test Blueprint (500 words max).
1. Define the constructs to be assessed by the test. Your test
should include at least two constructs and at least six items per
construct. Describe the relationship(s) between the constructs,
conceptually and statistically.
2. Specify the format of the items and response options.
3. Specify the content of the items. If a scale on your test
includes more than one kind of item, specify the number of items of
each type.
4. Specify the acceptable range of item statistics (mean or
proportion correct, standard deviation) for each item and test
statistics (mean, standard deviation, reliability) for each subscore.
E. Draft test. Provide a draft version of the test including
instructions and a full set of items that conform to parts 13 of the
test blueprint.
F. Proposed validation plan (750 words max). Describe five validation
studies for your test (one paragraph each). Design one study for each
of the five main sources of test validity evidence listed in the
Standards (content, response processes, internal structure,
relationships with other variables, and consequences of test use).
Explain the rationale behind the intended interpretation of the test
and how each study tests an assumption of that rationale (validity
argument).
G. Factor model (250 words max). Download the SPSS code for simulating
item response data from an assumed factor model. Enter plausible values
for the item parameters (loadings, error variances, intercepts, facor
correlation[s]). If necessary, tweak your values until your items
satisfy part 4 of the test blueprint. Report the final set of values in
a table. In the text, describe your general interpreation of the
resulting factor model. Include your interpretation of each factor, a
description of which items assess which factors, and a general
description of the strengths and weaknesses of the item set.
H. Pilot study (500 words max). Report this as if you had completed an
empirical pilot study, but use the simulated data from part G.
1. Conduct an item analysis of the data set. Report the item
statistics (means, standard deviations, item total correlations and
regression Rsquare values). Describe how differences between item
statistics relate to differences between item parameters in the factor
model.
2. Report the scale statistics (means, standard deviations).
Compare and constrast the scale statistics for each scale.
3. Report both alpha and lambda 2 reliability estimates.
Describe the alphasifitemdeleted.
4. Relate the results from parts H1 to H3 to the test blueprint.
Provide an overall evaluatoin of the functioning of the draft test
based on these results.
J. Appendices: Include the SPSS syntax used for your simulation as
Appendix A, and the SPSS output as Appendix B.
Convert your paper to portable document format (PDF), and
turn in both a hard copy and a PDF file. (If you cannot save directly
to PDF, download a free PDF print driver such as Cute PDF.) Note the due dates on
the course schedule. Proposals will be grading using the folloiwng
rubric.
Completeness (50% of grade, 13 points total)
A&B = 1 point
C = 1 point
D = 2 points. Each of four sections = .5 points.
E = 1 point.
F = 3 points.
G = 1 point.
H = 2 points. Each of four sections = .5 points.
J = 2 points.
Overall quality dimensions (50% of grade, 40 ponts total)
Clarity of presentation (1  10)
Technical accuracy of reporting (1  10)
Depth with which issues are presented within allowed space (1  10)
Overall conceptualization and design of proposed test and test
development (1  10)
15 = unsatisfactory.
6 = minimally satisfactory.
7 = some significant weaknesses.
8 = generally good with a few weak points.
9 = overall very well done.
10 = outstanding effort.
Grading: Each of the two examinations
is worth 25% of
your total grade. The course project is worth
another 30%. That leaves
20% for the homework
assignments. Letter
grades will be assigned as indicated below.



















