Chapter 6.2 Questions
A researcher is interested in differences in participation rates between boys and girls in interscholastic sports. She collects data from 1,000 girls and 1,000 boys from randomly selected high schools in the Illinois High School Athletic Association. Her data are compiled as follows: Participants: 170 boys 135 girls Nonparticipants: 830 boys 865 girls Which of the following is the appropriate statistical test to determine if participation rates differ by gender? a) t-test b) Pearson correlation c) two-way ANOVA d) Chi-square
A researcher is interested in differences in participation rates between boys and girls in interscholastic sports. She collects data from 1,000 girls and 1,000 boys from randomly selected high schools in the Illinois High School Athletic Association. Her data are compiled as follows: Participants: 170 boys 135 girls Nonparticipants: 830 boys 865 girls Which of the following is the appropriate statistical test to determine if participation rates differ by gender? d) Chi-square Chi-square is used with two categorical variables. In this scenario, both sex and participant status are categorical—the high-schoolers are categorized as either boy or girl, either participant or nonparticipant.
All of the following reflect variability in scores except a) variance. b) sampling frame. c) standard deviation. d) range.
All of the following reflect variability in scores except b) sampling frame. CORRECT The sampling frame is the target population for a study.
An IQ test is normally distributed with a mean of 100 and a standard deviation of 15. In this situation, 68% of students' IQ scores will fall between a) 90 and 120. b) 70 and 130. c) 85 and 115. d) 15 and 170.
An IQ test is normally distributed with a mean of 100 and a standard deviation of 15. In this situation, 68% of students' IQ scores will fall between c) 85 and 115. CORRECT The standard deviation is a measure of variability and indicates where scores will fall on a normal curve. In this case, because the mean of the test is 100, students with scores of 85-115 fall into the range of +/-1 deviations from the mean.
Complete the following analogy: descriptive statistics : inferential statistics :: a) variability : constant. b) conclusions : z-score. c) trends : generalizations. d) probability : central tendency.
Complete the following analogy: descriptive statistics : inferential statistics :: c) trends : generalizations. CORRECT Descriptive statistics reflect general tendencies in the data and can describe any variable: independent, dependent, control, or mediating. Inferential statistics allow us to compare or relate variables, test hypotheses, and examine the relationship among variables.
Hypothesis testing involves a) choosing the right statistical test. b) comparing data from normal distributions. c) testing differences between population parameters. d) comparing the observed value of a sample with population values.
Hypothesis testing involves d) comparing the observed value of a sample with population values. CORRECT This is the traditional way to test whether the sample mean is a good estimate of the population mean.
The same researcher is interested in a follow-up of the research described in the previous question. This time the research question addresses differences in enjoyment rates between boys and girls in interscholastic sports. She collects data from 100 girls and 100 boys who participate in high school sports from randomly selected high schools in the Illinois High School Athletic Association. She collects data by administering a 10- item sports-enjoyment scale she obtains from searching the ERIC database. The items on this scale range from 1 (very unenjoyable) to 5 (very enjoyable). She then computes the summed scale score for each participant. The range of scores for each student ranges from 10 to 50. Her data are compiled as follows: Participants: Boys, 31.4 Girls, 34.9 What statistical test would she use to determine if there is a gender difference in sports enjoyment? a) Pearson correlation b) Chi-square c) Two-way ANOVA d) t-test
The same researcher is interested in a follow-up of the research described in the previous question. This time the research question addresses differences in enjoyment rates between boys and girls in interscholastic sports. She collects data from 100 girls and 100 boys who participate in high school sports from randomly selected high schools in the Illinois High School Athletic Association. She collects data by administering a 10- item sports-enjoyment scale she obtains from searching the ERIC database. The items on this scale range from 1 (very unenjoyable) to 5 (very enjoyable). She then computes the summed scale score for each participant. The range of scores for each student ranges from 10 to 50. Her data are compiled as follows: Participants: Boys, 31.4 Girls, 34.9 What statistical test would she use to determine if there is a gender difference in sports enjoyment? d) t-test CORRECT A t-test is used to look for differences between two groups when the independent variable is categorical (in this case, boys/girls) and the dependent variable is continuous (in this case, the scores ranging from 10 to 50).
The scores on an algebra test for students in the third grade ranged from 45 to 95. We would say that this indicated a) a range of 50. b) a wide spread. c) a bell-shaped curve. d) variance.
The scores on an algebra test for students in the third grade ranged from 45 to 95. We would say that this indicated a) a range of 50. CORRECT Range is calculated by subtracting the lowest score in the dataset from the highest score in the dataset.
What would be the percentile score of a student whose standardized (z-score) on an intelligence test is +2? a) 68 b) 90 c) 99 d) 15
What would be the percentile score of a student whose standardized (z-score) on an intelligence test is +2? c) 99 CORRECT A z-score is a measure of relative standing. It has a mean of 0 and a standard deviation of 1. If a student's score falls 2 standard deviations above the mean, that student's score will fall in the 99th percentile.
What would be the percentile score of a student whose standardized (z-score) on the SAT is -1? a) 68 b) 50 c) 16 d) 98
What would be the percentile score of a student whose standardized (z-score) on the SAT is -1? c) 16 CORRECT A z-score of -1 means that a student did as well as or better than only 16% of the population.
Which of the following is a measure of relative standing? a) Percentile rank b) Variance c) Mean d) Median
Which of the following is a measure of relative standing? a) Percentile rank CORRECT Percentile rank describes the percentage of participants in the distribution with scores at or below a particular score.
Which of the following is an example of a type I error? a) An NCAA drug test that finds a tournament participant to have used illegal drugs when in fact she had not b) A false negative c) A true positive d) A lie-detection device that fails to identify former shoplifters for a retail employer
Which of the following is an example of a type I error? d) A lie-detection device that fails to identify former shoplifters for a retail employer CORRECT A type I error occurs when the null hypothesis is rejected by the researcher when it is actually true.
Which of the following is an example of a type II error? a) An NCAA drug test that finds a tournament participant to have used illegal drugs when she had not b) A false negative c) A lie-detection device that accuses a future employee of shoplifting for a retail employer when in fact he had not d) A false positive
Which of the following is an example of a type II error? b) A false negative CORRECT A type II error occurs when the researcher fails to reject the null hypothesis when an effect actually occurs in the population.
Which of the following statistical tests would be used to test mathematics achievement scores among students learning from the following three different pedagogical strategies: induction, theory only, theory plus examples? a) Standard deviation b) Analysis of variance c) Correlation analysis d) Chi-square analysis
Which of the following statistical tests would be used to test mathematics achievement scores among students learning from the following three different pedagogical strategies: induction, theory only, theory plus examples? b) Analysis of variance CORRECT Because the independent variable of pedagogical strategy includes three possible values—induction, theory only, theory plus examples—the appropriate test is analysis of variance.
