Quiz (Chapter 11)
Tests on Three or More Means
Using a OneWay ANOVA
Introduction
 "ANOVA" is an acronym. What's the full phrase it represents?
 What is the "statistical focus" of a oneway analysis of variance?
 A oneway analysis of variance can be used to compare ___ or more
groups.
 (T/F) ANOVA is the most frequently used inferential technique
for comparing three or more means.
The Purpose of a OneWay ANOVA
 A oneway ANOVA's inference goes from the __ (sample/population)
means to the __ (sample/population) means.
 If a oneway ANOVA involves 4 samples, each drawn from a different
population, how many inferences will the researcher be making on the
basis of the oneway ANOVA?
The Distinction Between a OneWay ANOVA and Other Kinds of ANOVA
 (T/F) These three terms are synonymous: "oneway ANOVA,"
"onefactor ANOVA," and "simple ANOVA."
 In discussing ANOVA studies, what term means the same thing as "independent
variable?"
 Correct this: A oneway ANOVA involves 3 independent variables, 2
dependent variables, and correlated samples.
 In Excerpt 11.9, what was the dependent variable?
 If research participants perform a task 3 times (first with no distraction,
then with a few distractions, and finally with many distractions),
the
independent
variable would be _____ (between/within)subjects in nature.
The OneWay ANOVA's Null and Alternative Hypothesis
 A oneway ANOVA's null hypothesis stipulates that ____ (at least
two/all) of the population means are equal.
 What was the null hypothesis in Excerpt 11.9? Explain it in words
first, then in symbols.
 A oneway ANOVA's alternative hypothesis says that ____ (at least
2/all) of the population means are different.
Presentation of Results
 In ANOVA summary tables, what do the abbreviations "SS" and "MS"
stand for?
 If an ANOVA summary table is set up for Excerpt 11.2, the "between
group" df will equal __.
 If the df for "total" is equal to 29, how many research
participants are involved in the analysis?
 What term other than "Error" is often used to label the middle row
of a oneway ANOVA summary table?
 If the df for Error = 12 while the SS for Error = 30, the MS for
Error would be equal to __.
 What letter is used to denote the calculated and critical values
in an analysis of variance?
 (T/F) Based on the information in Excerpt 11.19, it is possible
that the 3 samples were the same size.
 How many null hypotheses were tested in
Excerpt 11.12?
 In Excerpt 11.10, the Bonferroni adjustment technique was not applied.
If it had been applied, how many of the computed Fvalues would
have been statistically significant?
Assumptions of a OneWay ANOVA
 The 4 underlying assumptions of a oneway ANOVA are: randomness,
independence, normality, and _______.
 Using sumbols, show what the null hypothesis is when Levene's or
Hartley's test is applied to sample data.
 When testing an assumption, the researcher usually hopes to ____
(reject/fail to reject) the assumption's Ho.
 (T/F) The oneway ANOVA Ftest is robust to violations of the equalvariance
assumption if the ns are equal.
 If the normality or equalvariance assumption is untenable, the researcher
has 3 options. What are they?
Statistical Significance Versus Practical Significance
 Most researchers _____ (do/don't) attempt to see if their results
have practical significance once their ANOVA demonstrates that
they are the "owners" of statistical significance.
 What will a power analysis "tell" a researcher if the power analysis
is done before any data are collected?
Tips for Deciphering/Critiquing Research Results Based on OneWay ANOVAs
 In a oneway ANOVA: the statistical focus is on __, each subject
supplies __ score(s), and dftotal +
__ = the total number of research participants.
 (T/F) If the F is significant in a oneway ANOVA comparing three
groups, the researcher can legitimately infer (based on the sample evidence)
that m1, m2,
and m3 are all different.
 (T/F) If the F is not significant in a oneway ANOVA comparing three
groups, the researcher can legitimately infer (based on the sample evidence)
that m1, m2,
and m3 are all the same.
Questions that are Supposed to be More Difficult
 If a oneway ANOVA compares 3 groups (with each n=10), and if SSerror
= 54 while SStotal = 74, what will F be?
 Excerpt 11.22 does not contain an ANOVA summary table. If such a
table had been included, the numerical value for SStotal would
have been equal to ___ .
 What's the maximum number of numbers that can appear in a oneway
ANOVA summary table?
 In the study that provided Excerpt 11.22, what was the value of
n (assuming that the comparison groups were the same size)?
 If the researchers in Excerpt 11.23 had set their desired power
equal to 80% (rather than 95%), the needed sample size would have _______
. Options: a) been larger than 50; b) been smaller than 50; c) stayed
equal to 50
 In Excerpt 11.13, what happened to the size of each ANOVA's calculated
value as the Bonferroni adjustment technique was applied? Options:
a) It got larger; b) It got smaller; (c) It was unaffected by
Bonferroni
 In Excerpt 11.13, what happened to the size of each ANOVA's critical
value as the Bonferroni adjustment technique was applied? Options:
a) It got larger; b) It got smaller; (c) It was unaffected by
Bonferroni
 (T/F) These two symbolic statements say the same thing: (1) Ha:
sm2
0; (2) Ha:
sm2
> 0
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