Stats for Psych Exam 4

what is eta between

0-1

for an experiment comparing more than two treatment conditions you should use ANOVA rather than separate T test because

ANOVA has a less risk of a type 1 error

A treatment effect refers to differences between scores that are caused by the different treatment conditions. The differences produced by treatment effects will contribute to

MS between

what is the formula for eta

SS between/ Sstotal

When do you use the cohen's D

after rejecting null hypothesis

what does it mean to fail to reject the null hypothesis

agree with the null hypothesis that there is no statistical difference

What are the two measures of measuring effect size

cohen's d and percentage of variance explained

what does between-treatment variance look at

differences between sample means

what does the difference score measure

differences between scores not individuals

When a research randomly selects equivalent groups, and then exposes them to different stimulus conditions, and then measures them to see if significant differences can be observed, the total procedure is an example of

experimental research

True or False for a repeated-measures design, a separate sample is used for each treatment condition

false

True or False when there are more than two treatments in an ANOVA. rejecting the null hypothesis means that all of the treatments were significantly different from each other

false

True or False, One disadvantage of a repeated-measures design is that it typically requires more subjects than an independent measures design

false

True or false, In an analysis of variance MS total will always equal the sum of MSbetween or MSwithin

false

true or false, Post hoc tests are used after analysis of variance to determine why the null hypothesis was not rejected

false

what does the percentage of variance measure (r^2)

how much variability in the scores is explained by independent variable

how does the repeated measures reduce the problem of large individual differences

increases variability

definition of a factor

independent variable or quasi independent variable

In an ANOVA, which of the following is most likely to produce a large value for the F-ratio

large mean of differences and small sample variance

what does within-treatment provide

measure of how much difference is reasonable to expect by chance

what does the repeated measures or within subjects design measure

measures the same group of subjects on dependent variable twice

What does Tuckys Post Hoc test tell us

minimum distance between treatment that is necessary for significance

If your HSD number is smaller then it is

not significant

what is a level (treatment)

number of conditions

in a difference score, what is the degrees of freedom based on

number of sample scores

what are the three assumptions for independent measures anova

observations are independent, populations were samples were selected must be normal and have equal variances

what is a one-way (single factor design)

only involves one factor

when is a difference score used

repeated samples t test

what does Tuckys Post Hoc Test require

same sample size

if your HSD number is larger then it is

significant

what is a sample

subset of a population

what does it mean to reject the null hypothesis

there is a statistical difference

what is a population

total amount of people in an area

What are the differences in a between-treatment variance caused by

treatment (I.V) and due chance

What does the cohen's d measure

treatment effects in terms of standard deviation

True or False basic analysis in ANOVA involves partitioning the total variability into two components: between-treatments variability and within treatments variability

true

True or False the critical region for the F-ratio from an analysis of variance is located entirely in one tail of the distribution

true

True or False when the null hypothesis is true, the F-ratio is balanced so that the numerator and denominator are both measuring the same sources of variances

true

True or False, For an experiment with k=3 treatments, MS between =10. For this analysis SS between equals 20.

true

True or False, When a study involves more than two treatment conditions, an ANOVA will evaluate all of the separate mean differences in a single test

true

True or False, repeated measures experiment reduce the variance contributed by individual differences

true

true or false, in a matched subjects test, the subjects characteristics are matched before the study begins

true

true or false, in an analysis of variance, the term factor refers to an independent variable

true

true or false, variance is always positive

true

what does the matched subjects design measure

two separate samples

In an analysis of variance, the F-ratio is a ratio of

two variances

What does the within-treatment variance look at

variability in each sample

independent variable

variable that is manipulated

dependent variable

variable that is measured

what is an Anova based on

variance

What is the f anova formula

variance between sample means / variance expected by chance

what is the formula for difference score

x2-x1