Stats Test 1

In one0way ANOVA, two independent estimates of the common population variance, σ^2, are estimated. One estimate can be attributed to inherent differences between the c populations, while the other estimate can be attributed to

chance

What are the 3 assumptions for performing a one-way ANOVA?

1. The populations standard deviations are unknown but assumed equal 2. The populations are normally distributed 3. The samples are selected independently

Statistical inference concerning the mean differenced based on matched-pairs sampling required one of two conditions. what are they?

Both X1 and X2 are normally distributed

True or false: An ANOVA test determines if there is a difference in three of more population standard deviations?

False

The one-way analysis of variance (ANOVA) test si used to determine if differences exist between the ________ of three or more populations

Means

You reject Ho when ....

Test stat > crit or a> pvalue

True or false: One-way ANOVA analysis does not require that all means differ from one another

True

True or false: The two-way ANOVA test can be conducted with or without examining the interaction of the two factors

True

One of the disadvantages of Fisher's least difference (LSD) method is the probability of committing a

Type 1 error increases as the number of pairwise comparisons increases

In one-way ANOVA, within-treatments variability is based on

a weighted sum of the sample variance of each treatment

Matched-pairs sampling is an example of

dependent sampling

Between-treatment variability is based on a weighted sum of squared differences between the sample means and the

grand mean

We use ANOVA to determine

if differences exist between the means of three or more populations

Performing a one-way ANOVA test, instead of performing a series of two-samples t tests, _____________ the risk of incorrectly rejecting the null hypothesis

reduces

In ANOVA testing, if the ratio of the between-treatment variability to within-treatment variability is significantly greater than one, then me

reject the null hypothesis and conclude that not all population means are equal

A one-way ANOVA test is better than using a series of two-sample t tests because conducting a..

series of two-sample t tests inflates the risk of committing a Type 1 error

True or false: The one-way ANOVA test is based on F(df1,df2) distribution?

true

True or false: We use ANOVA to test for differences between population means by examining the amount of variability between the samples relative to the amount of variability within the samples

true

In one-way ANOVA within-treatments variability is base on the

variability within each sample

A type 1 error is

incorrect rejection of a true null hypothesis

In one-way ANOVA, the sum of squares due to treatments (SSTR) is the

sum of the weighted differences between the samples mean and grand mean