Psyc 210 E2 Review

How do you compute a person's percentile?

• convert the person's raw score to a z score

• convert the person's normalized score to a z score

• convert the person's z score into a raw score

• convert the person's z score into a normalized score

A z score ____ the mean will always be ____

• below; positive

• above; negative

• equal to; zero

• equal to; negative

What proportion of a normal distribution corresponds to a z score less than 1.25?

Suppose the average score on a standardized test for a population is 100 with a standard deviation of 15. A sample of 36 students takes the test, and their average score is 105. Calculate the z-statistic for this sample mean and determine the percentage of means that would fall below this sample mean

What is the difference between a z score and z statistic?

• the z score compares the group mean to the population while the z statistic indicates how far away a data point deviates from the mean

• the z score indicates how for away a data point deviates from the mean while the z statistic compares the group mean to a population

p level is also called...

• alpha

• beta

• varaibility

• central tendency

What does it mean for a hypothesis test to be robust?

• when it produces fairly accurate results, even if the assumptions underlying the hypothesis test are violated

• when it produces fairly inaccurate results because the assumptions underlying the hypothesis are violated

• when it produces fairly accurate results, even if the assumptions underlying the hypothesis are not violated

• when it produces fairly inaccurate results because the assumptions underlying the hypothesis are not violated

When is the null hypothesis rejected?

• the sample mean is smaller than the population mean

• the sample mean is larger than the population mean

• the p value is greater than the p level chosen

• the p value is smaller than the p level chosen

I hypothesize there will be a difference between in cold symptoms for two groups: A who took medicine and B who did not. Is this the research or null hypothesis?

• null

• research

The critical value(s) associated with a p level of 0.10 for a one tailed hypothesis test using the z statistic is (are):

• 1.282 or -1.282

• 1.282 and -1.282

• 2.327

• 1.645