Exam 8: Hypothesis Testing: Inferences About a Single Mean

A group of 200 students takes the Kaplan course in hopes that it will improve their SAT scores above the national mean of 500 on the math section.The population standard deviation of the SAT is known to be 100.Use an alpha level of .05 when answering the following questions.What should be the critical value?

If you conducted an experiment and observed results that indicated a very large discrepancy between the observed and expected results,then you probably would ______.

Rejection regions are determined with reference to an alpha level.

A sampling distribution of means based on all possible random samples of N=25,drawn from a population having a µ of 25 and a ó of 4,will have a mean of _____ and standard deviation of _____.

Distinguish between a Type I error and a Type II error.

The robustness of a test is influenced by several factors,including sample size,the degree of violation,and the form of violation.

The formula that we use to test the hypothesis that a simple mean was drawn from a population with µ=100 and ó=9 is _____.

A sampling distribution of means based on all possible random samples of size 25,drawn from a population with a mean of 100,will have a standard error of _____.

A researcher in sports psychology is interested in the resting pulse rate of long-distance college runners.She does some research and finds data from the U.S.Olympics team showing their long-distance runners have a resting pulse rate of 60 beats per minute.She wants to know if the pulse rate for college runners is different from the Olympic team's m of 60.She randomly samples 20 long-distance runners,and finds What value is obtained when calculating the test statistic?

When N > 40,and the raw scores in the population are normally distributed,then the normal and t distributions are very different from one another.

The null hypothesis is the hypothesis that we assume to be false for purposes of conducting a statistical test.

Why would a researcher want high statistical power rather than low statistical power?

If a researcher reports confidence intervals in a research report rather than results of traditional hypothesis,this researcher is utilizing the ____________________.strategy.

A group of 200 students takes the Kaplan course in hopes that it will improve their SAT scores above the national mean of 500 on the math section.The population standard deviation of the SAT is known to be 100.Use an alpha level of .05 when answering the following questions.What is the null hypothesis?

In a one-sample z-test,the term "statistically significant difference" tells you _____.

The set of all standard scores that are more extreme than the critical values (that is,less than the negative critical value or greater than the positive critical value.is called a(n)_____ region and constitutes a(n)_____ result.

A directional test is one designed to detect differences from a hypothesized population mean score in one direction only.

When there is exclusive concern that the population mean differs from a value in a specified direction,we should use _____.

Since they focus on two tails of the distribution,directional tests are often referred to as two-tailed tests.

Suppose you know that the mean score (m)on a measure of the personality trait "Openness to Experience" is 35.66 in a population of artists,with a standard deviation (s)of 13.32.Next,assume you went to Greenwich Village and gave this personality measure to a group of 10 artists.The mean in this sample was 40.33.You are interested in testing whether the 10 Greenwich Village artists were sampled from the same population described above.Calculate the 95% confidence interval.[Use a nondirectional test and an alpha level (a)of .05]