PSY 375 Exam 5
In a one-way ANOVA, a participant's score is +4 units from the value of GM. Additionally, her score is -1 units from her group's mean (M). How far from the GM is the M
+5 units
If x has SD² of 23.78 and y has SD² of 17.56, what is the standardized variance of x
1.00
If a person has an IQ of 130, approximately what percentage of people have higher IQs? Assume µ=100 and σ=15
2%
When figuring the variance of the distribution of means based on an estimated population variance in a sample with N=20, you divide the estimated population variance by ______
20
You are computing and independent means t test and find that s²pooled=250. If both N₁ and N₂=25, what is s²differences
20
If you have two samples of 15 people each, how many degrees of freedom will you have in your independent means t test
28
A consumer psychologists is interested in the effects of Annual income and Motivations to shop on shopping patterns of consumers. If Annual income (broken into two levels: High and Moderate) and Motivation to shop (with three levels: Escape, Necessity, and Socializing) are considered in one study, how many cells will there be
6
Each of the following is part of conducting a t test for independent means EXCEPT
A difference score is figured for each participant
In a factorial design, a "cell" is
A particular combination of levels of the variables that divide the groups
The Scheffe test is
A post-hoc comparison procedure
The test performed after the omnibus test in a one way ANOVA with three levels of the independent variable to determine precisely where the differences occurred is called
A post-hoc test
As compared to a t test for independent means, an analysis of variance
Can be used in any situation in which a t test for independent means would be used, but a t test for independent means cannot be used in all situations in which an analysis of variance would be used
Beta is the probability that
If the research hypothesis is true, the experiment would still fail to support it
β is the probability that
If the research hypothesis is true, the experiment would still fail to support it
A two-way factorial design
Is "two-way" because there are two variables that divide the groups whose influence is being studied
In day to day life, people informally form and test hypotheses. For example, one might wonder if attending every class causes students to get good grades or if it's that the variation between students (i.e., individuals differences) is more important regardless of whether they attend class or not? In this example, the variation between individuals
Is analogous to within-group variance
One characteristic of a F ratio is
It is never less than 0
In a 2 X 2 factorial ANOVA, you are testing
One interaction and two main effects
If your research hypothesis states that there is a difference between the means of three samples, you carry out a(n) _____ to test the null hypothesis that three populations have equal means
One-way ANOVA
Analyzing the data for your study requires that you complete a one-way ANOVA, which you do in SPSS. The output gives you an observed significance value of .032. Seeing this,you
Reject the null hypothesis
For a one-way ANOVA, SStotal= ______ + SSbetween
SSwithin
When computing an independent means t test, you find that s²m₁=14.58 and s²m₂=12.36. Based on this finding, you know that
Sample 2 has a larger N than Sample 1
If s²₁=200, s²₂=400, and s²pooled=325, what do we know about the respective sample sizes
Sample 2 is larger than sample 1
The median is greater than the mean in a distribution that is:
Skewed to the left
Suppose that you are interested in the relation between number of years working for a particular company and loneliness at work. You survey 40 workers at this company and figure a correlation between these two variables of -.90. This is considered a
Strong negative linear correlation
In a factorial analysis of variance, df(within) can be calculated by
Subtracting the number of cells from the total N, and summing the degrees of freedom of each individual cell (added up over all the cells) (Both A and C)
When conducting an analysis of variance, when the null hypothesis is true, then all of the following are true EXCEPT
The F ratio will generally be much larger than 1
A "distribution of differences between means" can be thought of as a distribution of
The differences you get when you repeatedly subtract a sample mean from one population from a sample mean from another population
When figuring the pooled population variance estimate in a t test for independent means
The estimates based on each of the samples are averaged in such a way as to give more influences to the estimate based on more participants
Statistics Student Susie is asked to find the most representative value for date containing income levels for the residents in her hometown. What value should she use
The median
In a 2 X 2 analysis of variance, the degrees of freedom for each main effect are
The number of levels of the variable minus 1
The sum of the squared deviations of each score from the mean of its group plus the sum of the squared deviations of each score's group mean from the grand mean equals
The sum of squared deviations of each score from the grand mean
When the ell means of a factorial design study are graphed, if the patterns of bards on one section of the graph are different from the pattern on the other section
There is an interaction effect
One important advantage of using effect sizes is that
They are a standardized score, making study to study comparison easier
The core idea of a one-way ANOVA is
To think of each score in terms of its deviation from the overall mean being divided into two parts
A 2 X 2 factorial design has
Two variables that divide the groups
Setting the significance level cutoff at .10 instead of the more usual .05 increases the likelihood of
Type I error
Failing to reject the null hypothesis when the research hypothesis is true is referred to as
Type II error
In a F ratio, the denominator is always the ______ group estimate of the population variance
Within
In a one-way ANOVA, ∑(x-M)² + ∑(M-GM)² =
∑(x-GM)²