Chapter 3 - review of univariate and bivariate statistics Flashcards
Are hypotheses tested about means or individual scores?
Means
Are distributions representing hypothetical states of reality distributions of means or distributions of individual scores
distributions of means
Is the mean of a population distribution, u, the same as the mean of a sampling distribution, u?
yes
Is the standard deviation of a population of individual scores, o, the same as the standard deviation of a sampling distribution?
No, sampling distributions have a smaller standard distribution than distribution of scores, and the decrease is related to N, the sample size.
What is the analysis of variance?
it is used to compare two or more means to see if there are any statistical differences among them
True or false, analysis of variance (ANOVA) is really a set of analytic procedures based on a comparison of two estimates of variance.
True
What are the two estimates of variance that ANOVA are based on?
One estimate comes from the differences among scores within each group, which is considered random or error variance.
Another estimate comes from differences in group means and is considered a reflection of group differences or treatment effects plus error.
What happens if the two estimates of variance in an ANOVA study differ appreciably?
It is concluded that they were drawn from different sampling distributions of means and the null hypothesis that the are the same is rejected.
What happens if the estimates of variance in an ANOVA study do not differ appreciably?
one concludes that all of the group means come from the same sampling distribution of means and that the slight differences among them are due to ransom error.
what is the numerator in a difference of variance ratio?
the difference among sample means is the numerator
what is the denominator in a difference of variance ratio?
the variance associated with error is the denominator
what is the name for the ratio between the two types of variances?
The F ratio
