PSYC 1010 Midterm 2 - Chapter 7 Questions and Answers Graded A+
Suppose you wanted to test the effects of the herbal supplement Echinacea on the length of colds. You
decide to infect 10 willing participants with the rhinovirus that causes the cold, and you then give them
Echinacea daily. Suppose you know that colds typically last 204 hours with a standard deviation of 36
hours. After collecting all of your data, you find that the average length of colds for your sample was 198
hours (although unlikely, assume that we were somehow able to determine the exact moment that a
cold begins and ends). Which of the following would provide the z statistic for this problem? -
Answers(198-204)/(36/sqrt10)
Which of the following would indicate null and research hypotheses for a two-tailed test? - AnswersH0:
µ1 = µ2; H1: µ1 ≠ µ2
When we calculate a z test, we will compare data from our sample with: - Answersa distribution
determined by our null hypothesis.
Under what conditions is it permissible to proceed with a hypothesis test, even though the assumption
that the dependent variable is measured on a scale measure is violated? - Answerswhen the data are
not clearly nominal or ordinal
Another name for a p level is a(n): - Answersalpha level
The quantitative subtest of the Graduate Record Exam (GRE) has a mean of 500 and a standard
deviation of 100. Scores from a sample of 25 students who enrolled in a study course yield a sample
mean score of 550. What is the percentile rank that corresponds to this sample? - Answers99.38
In one statistics course, students reported studying an average of 9.92 hours a week, with a standard
deviation of 4.54. Treating this as the population, what is the percentile for a student in the class who
studies for 10 hours a week? (Round the z score value to two decimal places.) - Answers50.70
Mehl (2007) published a study in the journal Science reporting the results of an extensive study of 396
men and women comparing the number of words uttered per day by each sex. If he were testing the
idea that women talk more than men do, what type of hypothesis test would Mehl conduct? -
Answersone-tailed
The null hypothesis states that: - Answersthe sample you are studying is not different from the
population from which it was drawn
Performing a z test involves comparing a(n): - Answersmean to a distribution of means
The p level is the: - Answersprobability with which a test statistic would occur if the null hypothesis were
true.
The percentile is the: - Answerspercentage of scores falling at or below a particular raw score.
Suppose you wanted to test the effects of the herbal supplement Echinacea on the length of colds. You
decide to infect 10 willing participants with the rhinovirus that causes the cold, and you then give them
Echinacea daily. Suppose you know that colds typically last 204 hours with a standard deviation of 36
hours. After collecting all of your data, you find that the average length of colds for your sample was 198
hours (although unlikely, assume that we were somehow able to determine the exact moment that a
cold begins and ends). Which of the following would provide the z statistic for this problem? -
Answers(198-204)/(36/sqrt10)
Which of the following would indicate null and research hypotheses for a two-tailed test? - AnswersH0:
µ1 = µ2; H1: µ1 ≠ µ2
When we calculate a z test, we will compare data from our sample with: - Answersa distribution
determined by our null hypothesis.
Under what conditions is it permissible to proceed with a hypothesis test, even though the assumption
that the dependent variable is measured on a scale measure is violated? - Answerswhen the data are
not clearly nominal or ordinal
Another name for a p level is a(n): - Answersalpha level
The quantitative subtest of the Graduate Record Exam (GRE) has a mean of 500 and a standard
deviation of 100. Scores from a sample of 25 students who enrolled in a study course yield a sample
mean score of 550. What is the percentile rank that corresponds to this sample? - Answers99.38
In one statistics course, students reported studying an average of 9.92 hours a week, with a standard
deviation of 4.54. Treating this as the population, what is the percentile for a student in the class who
studies for 10 hours a week? (Round the z score value to two decimal places.) - Answers50.70
Mehl (2007) published a study in the journal Science reporting the results of an extensive study of 396
men and women comparing the number of words uttered per day by each sex. If he were testing the
idea that women talk more than men do, what type of hypothesis test would Mehl conduct? -
Answersone-tailed
The null hypothesis states that: - Answersthe sample you are studying is not different from the
population from which it was drawn
Performing a z test involves comparing a(n): - Answersmean to a distribution of means
The p level is the: - Answersprobability with which a test statistic would occur if the null hypothesis were
true.
The percentile is the: - Answerspercentage of scores falling at or below a particular raw score.
