The analysis of variance (ANOVA) is a collection of statistical tests of the differences between groups that is mathematically related to t-tests.  In its basic form, ANOVA is a statistical test to see whether or not the means of several groups are equal.  So, it generalizes t-tests of more than two groups or variables.  If we wanted to see which of two classes had better test scores on a final exam, we might use a t-test; if we wanted to know which class in a large school had the best final exam score we might use the ANOVA analysis.  In Week Three, you will examine the one-way analysis of variance (ANOVA) and repeated measures design and compare those to the other tests of means from Week Two.  You will also have an opportunity to discuss a research question as well as to evaluate the best test to use to address that question statistically. Required Resources Read from the course text, Statistics for the Behavioral & Social Sciences: · Chapter 6: Analysis of Variance  · Chapter 7: Repeated Measures Designs for Interval Data Recommended Resources Article Statgraphics Centurion. (2006). Analysis of variance. Retrieved from http://www.statgraphics.com/analysis_of_variance.htm · This interactive website describes in detail how to use several types of ANOVA. It also includes examples and graphical displays. Websites 1.  VassarStats: Website for Statistical Computation . (http://vassarstats.net) · This is a website includes tools to calculate many of the statistical tests we cover in this course including t-tests, ANOVA, correlation, and regression.  Each calculator includes a tutorial and/or walkthrough.  2. Web Center for Social Research Methods. (http://socialresearchmethods.net) · This website includes links to numerous tools and tutorials relating to statistical concepts, calculations, and scale development. ANOVA Due Thursday by 18:00 hours In this 1 page paper, you will evaluate a research question and determine how that question might best be analyzed.  To do this, you will need to identify the appropriate application of course specified statistical tests, examine assumptions and limitations of course specified statistical tests, and communicate in writing critiques of statistical tests. A researcher wishes to study the effect of a new drug on blood pressure.  Consider and discuss the following questions as you respond:  · Would you recommend using a z-test, a t-test, or an ANOVA for the analysis?  Explain your answer. · What would your choice of test depend on?  For the test you select, explain your design and your comparison groups.  · Would the hypothesis be directional or non-directional?  · Would the test be one-tailed or two-tailed?  · What would be the null and what would be the alternative hypothesis? · Provide references on separate page This last part should be on a separate sheet of paper…alone with references. How does the number of groups being compared affect the statistical analysis? What suggestions would you make ...

1. The analysis of variance (ANOVA) is a collection of statistical
tests of the differences between groups that is mathematically
related to t-tests. In its basic form, ANOVA is a statistical test
to see whether or not the means of several groups are equal. So,
it generalizes t-tests of more than two groups or variables. If
we wanted to see which of two classes had better test scores on
a final exam, we might use a t-test; if we wanted to know which
class in a large school had the best final exam score we might
use the ANOVA analysis.
In Week Three, you will examine the one-way analysis of
variance (ANOVA) and repeated measures design and compare
those to the other tests of means from Week Two. You will also
have an opportunity to discuss a research question as well as to
evaluate the best test to use to address that question
statistically.
Required Resources
Read from the course text, Statistics for the Behavioral & Social
Sciences:
· Chapter 6: Analysis of Variance
· Chapter 7: Repeated Measures Designs for Interval Data
Recommended Resources
Article
Statgraphics Centurion. (2006). Analysis of variance. Retrieved
from http://www.statgraphics.com/analysis_of_variance.htm
· This interactive website describes in detail how to use several
types of ANOVA. It also includes examples and graphical
displays.

2. Websites
1. VassarStats: Website for Statistical Computation .
(http://vassarstats.net)
· This is a website includes tools to calculate many of the
statistical tests we cover in this course including t-tests,
ANOVA, correlation, and regression. Each calculator includes
a tutorial and/or walkthrough.
2. Web Center for Social Research Methods.
(http://socialresearchmethods.net)
· This website includes links to numerous tools and tutorials
relating to statistical concepts, calculations, and scale
development.
ANOVA
Due Thursday by 18:00 hours
In this 1 page paper, you will evaluate a research question and
determine how that question might best be analyzed. To do
this, you will need to identify the appropriate application of
course specified statistical tests, examine assumptions and
limitations of course specified statistical tests, and
communicate in writing critiques of statistical tests.
A researcher wishes to study the effect of a new drug on blood
pressure. Consider and discuss the following questions as you
respond:
· Would you recommend using a z-test, a t-test, or an ANOVA
for the analysis? Explain your answer.
· What would your choice of test depend on? For the test you
select, explain your design and your comparison groups.
· Would the hypothesis be directional or non-directional?
· Would the test be one-tailed or two-tailed?
· What would be the null and what would be the alternative
hypothesis?
· Provide references on separate page
This last part should be on a separate sheet of paper…alone
with references.

3. How does the number of groups being compared affect the
statistical analysis? What suggestions would you make for
change or improvement? Why would these suggestions
potentially be more useful?
Discussion 1 –ANOVA– Evaluate the methods, results,
limitations, and assumptions of an article utilizing
ANOVA. Examine the difference between one- and two-tailed
hypothesis tests.
When grading the ANOVA discussion I will be looking for your
answer to contain:
Week 3 Paper 1 Board Rubric
Earned
Weight
Content Criteria
0.5
Student identifies the groups in their test for blood pressure.
Student identifies and defines which test they will use to test
their groups. Provides support for why this test was chosen.
0.5
Student defines one tailed and two tailed t-tests and identifies
which is used in their experiment.
0.5
Student defines directional and non-directional hypothesis and
identifies which is used in their experiment.
0.5
The student responds to at least two classmates’ initial posts by
Day 7.

4. 1
Format
2
Student uses correct spelling, grammar and sentence structure.
Total
5
Intellectual Elaboration:
Last week we looked at standard deviation and the z-score as
ways to look at different data distributions but be able to
compare them as equals and how inferential statistics work.
This week we will look at inferential statistics, specifically the
ANOVA.
Similar to the t-test is the Analysis of Variance (ANOVA) also
allows us to statistically see if the independent variable(s) (IV)
have an effect on the dependent variable (DV). Unlike the t-test
the ANOVA allows us to look at more than one IV if needed to
test for statistical effect. The one-way ANOVA is similar to the
one way t-test, both are looking at the one DV and one IV to
determine if there is any statistically significant change. The
benefit of the ANOVA is that it will allow direct comparison of
multiple groups (with multiple IV’s) instead of separate t-test
for each comparison. Within an ANOVA a post-hoc test is used
to determine which groups being tested are statistically
different from one another (Tanner, 2012).
Repeated measures, also known as the within-subject design, in
a ANOVA is how we test to see if the means are the same or
different when we correlate data from subjects within the same
groups instead of between groups (Choudhury, 2009). What
this means is that you can test the mean of the same variable
across different points of time, or you can test the mean of the

5. same variable across different conditions (Lund Research,
2012). For example if testing the HIV drug you could test mean
of the DV (white blood cell count) across a 3 month, 6 month,
and 12 month period. If you want to test Drug X under different
conditions you could test the drug alone, and paired with
medication A and medication B. This test is an extension of the
t-test and looks to see if there are differences within the
mean(s) being tested. When looking at what the results mean
when using repeated measures you will either accept the null
hypothesis (there is no change) or choose the alternative
hypothesis. The way you will do this is with a post hoc test or
HSD (honesty significantly different). The HSD will give you
the minimum difference between the two means being tested to
determine if they are significantly different. If there is a
statistical significance you will not accept the null hypothesis
(Tanner, 2011).
Additional Resources (web links, videos, and articles):
ANOVA – With Independent Samples
http://www.youtube.com/user/EducatorVids2?v=NiAlbPv4pEQ
&feature=pyv
Repeated Measures ANOVA:
https://statistics.laerd.com/statistical-guides/repeated-measures-
anova-statistical-guide.php
References:
Choudhury, A (2009). Repeated Measures ANOVA. Retrieved
from Experiment Resources: http://www.experiment-
resources.com/repeated-measures-anova.html
ChangingMinds.org. (2012) t-test. Retrieved
from http://changingminds.org/explanations/research/analysis/t-
test.htm
Lund Research Inc. (2012) Repeated measures ANOVA.
Retrieved from https://statistics.laerd.com/statistical-
guides/repeated-measures-anova-statistical-guide.php
Tanner, D. (2011). Statistics for the behavioral & social
sciences. San Diego, CA: Bridgepoint Education, Inc.

6. Assignment
When you are writing your ANOVA Critique paper this week I
want you to use the following format:
I. Introduction – What is an ANOVA and what is
the research problem and hypothesis of the article?
II. Methods – Who are the subjects and variables
within the article?
III. Results – What is the statistical analysis used,
why were these tests chosen? What were the results of these
tests and what do they mean?
IV. Discussion – What were the strengths of this
article? What would you have done differently in terms of
variables and statistical analysis? Why?
V. Conclusion – Reiterate the introduction and
include relevant information that answers the questions
regarding the hypothesis.
ANOVA Article Critique
Read the article "Cognitive Effects of Risperidone in Children
with Autism and Irritable Behavior," and identify the research
questions and/or hypotheses as they are stated. Consider the
following questions: What are the variables (sample sizes,
population, treatments, etc.)? How was the analysis of variance
used in this article (and what type of ANOVA was used)?
Write a two- to three-page paper presenting the information
listed below. In addition, provide a title page and reference
page in APA style. Cite any references made to the article
within the body of the paper in APA style. Your paper should
begin with an introductory paragraph (including a thesis
statement) and end with a concluding paragraph summarizing
the major points made in the body of the paper and reaffirming
the thesis.
Carefully review the Grading Rubric for the criteria that will be
used to evaluate your assignment.

7. The body of your paper must:
1. Determine what question(s) the authors are trying to answer
by doing this research.
2. Determine the hypothesis being tested and the concepts that
were applied in this process.
3. Evaluate the article and critique the statistical analysis
employed in the study. Would you have included more and/or
different variables? Explain your answer.
4. Examine the assumptions and limitations of the statistical
study. What would you have done differently in this case?
Explain your answer.
5. Identify how the authors applied statistical testing to the
problem.
6. Interpret the findings of the author(s) using statistical
concepts.
Access the Critical Thinking Community website for tips on
how to formulate your thoughts and discussion of these
questions in a logical and meaningful manner.
Writing the Article Critique
The Assignment:
1. Must be two to three double-spaced pages in length
(excluding title and reference pages), and formatted according
to APA style as outlined in the Ashford Writing Center.
2. Must include a title page with the following:
a. Title of paper
b. Student’s name
c. Course name and number
d. Instructor’s name
e. Date submitted
3. Must document all sources in APA style as outlined in the
Ashford Writing Center.
4. Must include a separate reference page formatted according

8. to APA style as outlined in the Ashford Writing Center.
5. Choudhury, A (2009). Repeated Measures ANOVA. Retrieved
from Experiment Resources: http://www.experiment-
resources.com/repeated-measures-anova.html
6. ChangingMinds.org. (2012) t-test. Retrieved
from http://changingminds.org/explanations/research/analysis/t-
test.htm
7. Lund Research Inc. (2012) Repeated measures ANOVA.
Retrieved from https://statistics.laerd.com/statistical-
guides/repeated-measures-anova-statistical-guide.php