Chapter 13

The variability due to chance, also known as within-treatments variability, is the estimate of 2 which is based on the:

C. variability of the data within each sample

Tukey's honestly significant differences (HSD) method uses ____ instead of ____ when compared to Fishers least differences (LSD) method for pairwise comparisons.

D. studentized range values; t values

The between-treatments variability is the estimate of 2 which is based on the variability due to chance.

False

Fisher's 100(1 - )% confidence interval for the difference between two population means i - j is:

b

Fisher's least difference (LSD) method is applied when the:

b. ANOVA test has rejected the null hypothesis of equal population means

When using Fisher's least significant difference (LSD) method at some stated significance level, the probability of committing a Type I error increases as the number of:

b. pairwise comparisons increases

In a two-way ANOVA test, how many null hypotheses are tested?

c. 2 or 3

Which of these null hypotheses is applicable for a two-way ANOVA test with interaction?

c. There is no interaction between factors A and B.

If there are five treatments under study, the number of pairwise comparisons is:

10

Tukey's honestly significant differences (HSD) method ensures that the probability of a Type I error remains fixed irrespective of the number of:

A. pairwise comparisons

Identify the assumption that is not applicable for a one-way ANOVA test.

B. The population standard deviations are not all equal

One-Way ANOVA analyzes the effect of one factor on the population mean. It is based on a:

B. completely randomized design

ANOVA is a statistical technique used to determine if differences exist between the means of two populations.

False

If units within each block are randomly assigned to each of the treatments, then the design of the experiment is referred to as a completely randomized design.

False

In general, blocks are the levels at which we hold an integral factor fixed, so that we can measure its contribution to the variation within the samples.

False

When the null hypothesis is rejected in an ANOVA test, Fisher's least significant difference method is superior to Tukey's honestly significant differences method to determine which population means differ.

False

When using Fisher's LSD method at some stated significance level a(alpha), the probability of committing a Type I error increases as the number of pairwise comparisons increases.

True

Which of the following is the correct interpretation of the Fisher's 100(1 - a(alpha))% confidence interval for µi - µj?

c. If the interval does not include the value zero, the null hypothesis, that H0: µi - µj = 0, is rejected at alpha level of significance

if the interaction between two factors is not significant, the next tests to be done are:

c. Tests about the population means of factor A or factor B using two-way ANOVA without interaction.

If the amount of variability between treatments is significantly greater than the amount of variability within treatments, then:

A. reject the null hypothesis of equal population means

Between-treatments variability is based on a weighted sum of squared differences between the:

B. sample means and the overall mean of the data set

When two factors interact, the effect of one factor on the population mean depends upon the specific value or level present for the other factor.

True

One-way ANOVA analyzes the effect of one factor on the population mean and it is based on a completely randomized design.

True

The interaction test is performed before making any conclusions based on the tests for the main effects.

True

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

Tukey's 100(1 - a(alpha))% confidence interval for the difference between two population means µi - µj for balanced data is given by _____ .

b

If units with each block are randomly assigned to each of the treatments, then the design of the experiment is referred to as a:

c. randomized block design

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

dD. Type I error increases as the number of pairwise comparisons increases.