PS211 Exam 3

Analysis of variance, family of statistical tests

ANOVA means ____ and is a ____

Subtracting the mean of the population (0 assuming the null is true) from the mean difference and dividing that value by the sample standard error

Cohen's d can be calculated for a paired samples t by ____

Subtracting the mean score in condition 1 from the mean score in condition 2 and dividing that value by s pooled

Cohen's d can be calculated for an independent samples t by ____

Taste-testing

a classic within-groups design is ____

One-way ANOVA

a hypothesis test that includes both one nominal independent variable with more than two levels and a scale dependent variable

Two-way ANOVA

a hypothesis test that includes two nominal independent variables, regardless of their numbers of levels, and a scale dependent variable

Statistical power

a measure of the likelihood that we will reject the null hypothesis, given that the null hypothesis is false

Counterbalancing

a method of controlling for order effects in a repeated measure design by either including all orders of treatment or by randomly determining the order for each subject

Number of participants - 1

a trick to determine the total degrees of freedom is ____

Cohen's d

a very common effect size indicator that expresses effect size in terms of standard deviation; standardized difference between means

Still focusing on a ratio of between-group and within-group variance, same 6-step process, similar assumptions

similarities between ANOVAs and t-tests include ____, ____, and ____

Impossible, unethical, impractical

sometimes within-subjects studies are ____, ____, or ____

Meta analysis

studies that involve the calculation of a mean effect size from the individual effect sizes from multiple studies

Posthoc tests

tests that help you identify where the specific differences are after running an ANOVA

More conservative, can be used in many situations

the Bonferroni correction is ____ and ____

R^2

an estimate of the proportion of variance in the DV that is accounted for by the independent variable

Tukey HSD (honestly significant difference)

determines the differences between the means in terms of standard error

Type II error

failing to reject a false null hypothesis

Source table

helps researchers organize the most important calculations necessary to conduct an ANOVA as well as the final results

Tukey's HSD

if equal variances is not violated, run a ____

Games-Howell

if equal variances is violated, run a ____

Order effects

occur when the order in which the participants experience conditions in an experiment affects the results of the study

Homoscedasticity

population variance in the DV is the same at each level of the IV

Heteroscedasticity

populations are those that have different variances

A significant F statistic is found

posthoc tests can only be run if ____

Bonferroni correction

reduce type I error by dividing alpha by # of tests to give new alpha for finding the t-critical value

Type I error

rejecting null hypothesis when it is true

Partial eta squared

similar to R^2, explains how much variance can be explained by the IV

First finding the grand mean by finding the mean of all values across conditions and finding SStotal, then find SSwithin using the mean of the group that the participant comes from, then find SSbetween using the mean of the group that the participant comes from (same value for each row of each separate group), then find dfbetween, dfwithin, and dftotal, then find the two MS values, and finally divide MSbetween by MSwithin to find the F-statistic

the F-statistic for the one-way between-groups ANOVA can be calculated by ____

First finding the grand mean by finding the mean of all values across conditions and finding SStotal, then find SSbetween using the mean of the group that the participant comes from (same value for each row of each separate group), then find SSsubjects using the mean of each participant's responses across conditions, then find SSwithin, then find dfbetween, dfwithin, dfsubjects, and dftotal, then find the three MS values, and finally divide MSbetween by MSwithin to find the F-statistic (F-subjects isn't important for NHST)

the F-statistic for the one-way within-groups ANOVA can be calculated by ____

Dividing SSbetween by SStotal

the R^2 effect size for the one-way between-groups ANOVA can be calculated by ____

Dividing SSbetween by (SStotal - SSsubjects)

the R^2 effect size for the one-way within-groups ANOVA can be calculated by ____

Unexplained variance

the amount of variation in the dependent variable that cannot be accounted for by the combination of independent variables

F-distribution

the comparison distribution for one-way between-groups and one-way within-groups ANOVAs is the ____

Publication bias

the fact that in the current climate, studies with significant findings are more likely to be published than studies without significant findings

Is the dependent variable scale?, is the data randomly selected from the population?, are the data normally distributed?, do the populations have the same variance? (homoscedastic vs. heteroscedastic), is there counterbalancing?

the five assumptions for a one-way within-groups ANOVA are ____, ____, ____, ____, and ____

Is the dependent variable scale?, is the data randomly selected from the population?, are the data normally distributed?, do the populations have the same variance? (homoscedastic vs. heteroscedastic)

the four assumptions for a one-way between-groups ANOVA are ____, ____, ____, and ____

Select a topic of interest and determine your inclusion criteria, locate ALL studies that meet your criteria, calculate an effect size for each study (often Cohen's d), calculate summary statistics, create a visual display of the effect sizes, and conduct a hypothesis test

the four main steps of meta analysis are ____, ____, ____, and ____

Things that increase the area under the curve beyond the cutoff, things that decrease standard error, things that reduce unexplained variance, things that exaggerate the mean difference between levels of the IV

the main categories of factors that influence power include: ____, ____, ____, and ____

Choose the appropriate hypothesis test, state the null and research hypotheses in words, determine the characteristics of the comparison distribution, determine the critical values, calculate the test statistic, decide whether to reject or fail to reject the null hypothesis

the six main steps of hypothesis testing include: ____, ____, ____, ____, ____, and ____

Differences between means, variance explained

the two main types of effect sizes express the size of the effect in terms of ____ and ____

0.2, 0.5, 0.8

the typical convention for Cohen's d values is that ____ is small, ____ is medium, and ____ is large

0.01, 0.06, 0.14

the typical convention for R^2 values is that ____ is small, ____ is medium, and ____ is large

Increase N, decrease standard deviation

things that decrease standard error include: ____ and ____

Increase alpha, use a one-tailed test instead of a two-tailed test (not relevant for ANOVAs)

things that increase the area under the curve beyond the cutoff include: ____ and ____

Repeated measures ANOVA

this one-way ANOVA uses correlated groups of participants or every participant goes through multiple conditions

Numerator degrees of freedom (between-groups), denominator degrees of freedom (within-groups)

to determine critical values for the F-statistic, use the intersection of the ____ and the ____

Forest plot

type of diagram used to present the meta-analysis results of studies with dichotomous outcomes; plots mean differences

The Levene's Test significance is less than 0.05, the Levene's Test significance is not less than 0.05

when running a one-way between-subjects ANOVA on SPSS, equal variances is violated if ____ and equal variances is not violated if ____

There was a statistically significant difference between groups as determined by a one-way between groups ANOVA, F(2,27) = 4.467, p = .021, ηp2 = 0.12, C: 16.8 - 32.4. The data did not reveal a violation of equal variance, therefore Tukey's HSD post hoc tests were performed. The multiple comparisons found that the time to complete the problem was significantly lower after taking the intermediate (Mean =23.40, SD = 3.20 (min), p =0.03) course compared to the beginners' course (Mean = 27.20, SD = 3.00 (min)). There was no statistically significant difference between the intermediate and advanced groups (p =0 .99). Overall, we find that the effect of preparation as evidenced by the type of course completed can have a significant effect on the amount of time required to solve problems.

when writing up a results section for an ANOVA: ____

Games-Howell

when you have unequal variances and unequal sample sizes, an attractive post-hoc procedure is the

Partial eta squared, eta squared

when you only have 1 IV, ____ and ____ are the same