Exam 12: Sampling Distributions, Sampling Distribution of the Mean: the Normal Deviate Z Test

If one draws two samples of size N from a distribution of raw scores (with replacement), then the means of the two samples will _________.

Write the number of the symbol shown in Column 1 in the space provided to the left of the term in Column 2 that it represents.

An English teacher has been teaching a sixth grade composition class for many years. He has the feeling that over the past several years, the writing ability of students has changed. A national test of proficiency in composition was administered 5 years ago. The resulting distribution of scores was normally shaped, had a mean of 85 and a standard deviation of 10.9. In order to test his feeling, he gives his present class of 43 students the same proficiency test. The resulting mean is 80 and the standard deviation is 8.7.

Power is an esoteric topic that has very little practical utility.

As N increases, the variability of the sampling distribution of the mean increases.

Increasing N usually results in an increase of power.

If we take all possible samples from a normally distributed population, which of the following sample sizes will yield the smallest variation in the means of the samples?

For the population and sample size given in question 8, the standard error of the mean equals _________.

The area under the critical region for rejection must _________.

Define µ null and µ real .

Define sampling distribution of a statistic.

The sampling distribution of z must be normally distributed to use the z test.

What are the assumptions underlying the z test?

Power is the sensitivity of the experiment to detect a real effect of the independent variable, if there is one.

The formula for z obt for the sampling distribution of the mean is .

If H 0 is false, a high level of power increases the probability we will reject it.

Define critical values of z.

Define critical region.

If one draws all possible samples for various values of N from the same population of raw scores, as N increases _________.

If there is a real effect, the higher the power, the more likely H₀ will be rejected.