STAT 3342 exam II true/false

In a two-sample t-test, the number of degrees of freedom for the test statistic increases as the sample size increases

True

The F distribution is skewed and has a mean close to 1

True

The standard normal (z) score may be used for inferences concerning population proportions

True

The uses of paired samples allows for control of variation because each pair is subject to the same common source of variability

True

With the usual ANOVA assumptions, the ratio of the mean squares whose expected values are the same has an F distribution

True

The pooled variance estimate is used when comparing means of two populations using independent samples

True (provided the variances are equal)

When two means of two independent samples are used to compare two population means, we are dealing with dependent (paired) samples

False; When two means of two independent samples are used to compare two population means, we are dealing with independent samples

To apply the f test in ANOVA, the sample size for each factor level (population) must be equal

False; don't need to be equal

To apply the f test in ANOVA, the sample standard deviation for each factor level (population) must be equal

False; don't need to be equal

It is not necessary to have equal sample sizes for paired tests

False; it is necessary to have equal sample sizes for paired tests

One of the assumptions underlying the use of (pooled) two-sample test is that the samples are drawn from populations having equal means.

False; one assumption is that the pop. variances are equal

If every observation is multiplied by 2, then the test statistic is multiplied by 2

False; If every observation is multiplied by 2, then the test statistic increases

The Chi Squared distribution is used for making inferences about 2 population means

False; The F distribution is used for making inferences about 2 population means (chi squared for single variance)

If the treatments in a CRD consists of numeric levels of input to a process, the LSD multiple comparison procedure is most appropriate

False; the LSD is valid for a given a comparison only if the LSD is used for I depended comparisons or pre-planned comparisons

The F distribution is symmetric about a mean of 0

False; the T distribution is symmetric about a mean of 0

The F distribution is used for testing differences between means of paired samples

False; the T distribution is used for testing differences between paired samples

To use the F statistic to test for the equality of two variations, the sample size must be equal

False; the populations variances must be equal

A two-sample test is twice as powerful as a one sample test

False; they are equally powerful

The logarithmic transformation is used when the variance is proportional to the mean

False; when standard deviation is proportional to the mean

If the calculated value of the test statistic is negative, then there is a strong evidence that the null hypothesis is flass

False; you can calculated a negative test statistics and still fail to reject the null

If every observations is multiplied by 2, the the value of the ANOVA 8/ multiplied by 4

Riggs False; rest of the world True

A set of sample means is more likely to result is rejection of the hypothesis of equal population means of the variability within the population is small

True