MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
expand_more
expand_more
format_list_bulleted
Question
A group of 20 college students participated in a study to examine the effects of a new study technique on their exam performance. Each student's exam score before and after implementing the new study technique was recorded. The average difference between the exam scores before and after implementing the new study technique was found to be 7 points higher after the technique was applied. The variance of the differences for the entire sample was calculated to be 36. Is there a significant difference in the exam scores before and after implementing the technique? Use a two-tailed test at alpha.05.
SAVE
AI-Generated Solution
info
AI-generated content may present inaccurate or offensive content that does not represent bartleby’s views.
Unlock instant AI solutions
Tap the button
to generate a solution
to generate a solution
Click the button to generate
a solution
a solution
Knowledge Booster
Similar questions
- Students in one class are asked to complete the same questionnaire 3 times throughout the semester: at the beginning, at the midterm, and at the end. The purpose of the questionnaire is to track students' perception of their progress at different points in the semester. Scores at Time 1 (beginning of the semester), Time 2 (midterm), and Time 3 (end of semester) are compared against one another. What type of analysis of variance would be appropriate for examining the results from this dataset?arrow_forwardA factor in determining the usefulness of an examination as a measure of demonstrated ability is the amount of spread that occurs in the grades. If the spread or variation of examination scores is very small, it usually means that the examination was either too hard or too easy. However, if the variance of scores is moderately large, then there is a definite difference in scores between "better," "average," and "poorer" students. A group of attorneys in a Midwest state has been given the task of making up this year's bar examination for the state. The examination has 500 total possible points, and from the history of past examinations, it is known that a standard deviation of around 60 points is desirable. Of course, too large or too small a standard deviation is not good. The attorneys want to test their examination to see how good it is. A preliminary version of the examination (with slight modifications to protect the integrity of the real examination) is given to a random sample of…arrow_forwardAn analysis of variance produces SSb = 40 and MSb = 20. In this analysis, how many treatment conditions are being compared?arrow_forward
- Earlier this semester, we learned to use 2-Sample-TTest to compare the population means of two independent populations. One-way ANOVA is more powerful because it could compare the population means of three or more independent populations. However, use of one-way ANOVA also requires the assumption that the populations have the same variance. In this exercise, we will compare and contrast One-way ANOVA and 2-Sample-TTest. With the 2-Sample- TTEST, we will first choose 'No' for the pooled variances option, then re-run the test while choosing 'Yes' for the pooled variances option. Use the following data to complete these tasks. Depending on if you choose to do this by hand or using code, use the data format that suits you best - LONG form on top or WIDE form on bottom. Treatment One One One One One One One Two Two Two Two Two Two Two Treatment One 7.1 8.5 7.6 7.7 6.9 8.5 7.8 Response 7.1 8.5 7.6 7.7 6.9 8.5 7.8 1.4 4.1 4.3 3.9 4 4 4.6 p-value= Treatment Two 1.4 4.1 4.3 3.9 4 4 4.6 1. Use…arrow_forwardA social psychologist is interested in knowing whether people are more aggressive if they are in the presence of a weapon, such as a gun Treatment Condition- T1, as compared to when they are in a room with an innocuous item such as a tennis racket Control Condition-T2. The study used one sample of 17 college students and had all of the students in the sample participate in both treatment conditions. The mean of the difference scores was 18.0 and the variance (s2) was 612. An alpha level of .01 was set. Calculate the t. A 3.000 B 2.780 C 2.152 D 1.765arrow_forwardGetting an adequate amount of sleep can improve a variety of physiological functions, and it is known that the average number of hours that people sleep each night is normally distributed. A psychiatrist or a major research center takes an SRS of 25 emotionally disturbed patients and records the average amount of sleep that each gets on a typical night. He summarizes the data and finds that Xbar=6.90 and S= 0.878. What sample size would the researcher need to use in order to decrease the margin of error of a 95% confidence interval to +-0.20 hours?arrow_forward
- A factor in determining the usefulness of an examination as a measure of demonstrated ability is the amount of spread that occurs in the grades. If the spread or variation of examination scores is very small, it usually means that the examination was either too hard or too easy. However, if the variance of scores is moderately large, then there is a definite difference in scores between "better," "average," and "poorer" students. A group of attorneys in a Midwest state has been given the task of making up this year's bar examination for the state. The examination has 500 total possible points, and from the history of past examinations, it is known that a standard deviation of around 60 points is desirable. Of course, too large or too small a standard deviation is not good. The attorneys want to test their examination to see how good it is. A preliminary version of the examination (with slight modifications to protect the integrity of the real examination) is given to a random sample of…arrow_forwardA clinical psychologist wants to compare the efficacy of medication versus Cognitive Behavioral Therapy. He specifically believes that medication will reduce the frequency of suicidal ideation more than Cognitive Behavioral Therapy. He finds that the medicated group (n = 22) reports an average of 1.84 suicidal thoughts, with a sample variance = 9.01. The CBT group (n = 22) reports an average of 3.92 with a sample variance of 9.13. What would be the test statisitc the clinican observes given this data? (Be sure to round your answer to the second decimal place). "arrow_forwardA study aims to compare the social media usage rates of men and women. Nine men and 9 women are drawn from the general population and the average time (in minutes) they spent on social media each day was compared (men’s mean = 40, sum of squares = 153; women’s mean = 48, sum of squares = 216). What is the (a) estimated population variance for each random sample, and (b) pooled variance? Estimated population variances = 19.13 and 27.00; Pooled variance = 23.07 Estimated population variances = 19.13 and 27.00; Pooled variance = 20.50 Estimated population variances = 17.00 and 24.00; Pooled variance = 20.50 Estimated population variances = 17.00 and 24.00; Pooled variance = 23.07arrow_forward
- A researcher is interested whether a new drug is effective in changing patients' cholesterol levels. She divided 33 patients into 3 groups according to the dosage the patient received. The cholesterol levels of all patients are measured and used as the data for the Analysis of Variance (ANOVA). If she reported the test statistic F = 2.1 What is the degree of freedom for the numerator of the F statistic? What is the degree of freedom for the denominator of the F statistic? What is the P-value of the F-test? (Round to 3 decimals) Given the significance level of 0.01, what can she conclude from the test? *The patients in differnt groups have simliar average cholesterial levels. The drug made no difference. *At least one group of patients have an average cholesterol level that is different from the other groups. The drug may have an effect.arrow_forwardA factor in determining the usefulness of an examination as a measure of demonstrated ability is the amount of spread that occurs in the grades. If the spread or variation of examination scores is very small, it usually means that the examination was either too hard or too easy. However, if the variance of scores is moderately large, then there is a definite difference in scores between "better," "average," and "poorer" students. A group of attorneys in a Midwest state has been given the task of making up this year's bar examination for the state. The examination has 500 total possible points, and from the history of past examinations, it is known that a standard deviation of around 60 points is desirable. Of course, too large or too small a standard deviation is not good. The attorneys want to test their examination to see how good it is. A preliminary version of the examination (with slight modifications to protect the integrity of the real examination) is given to a random sample of…arrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
- Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman
MATLAB: An Introduction with Applications
Statistics
ISBN:9781119256830
Author:Amos Gilat
Publisher:John Wiley & Sons Inc
Probability and Statistics for Engineering and th...
Statistics
ISBN:9781305251809
Author:Jay L. Devore
Publisher:Cengage Learning
Statistics for The Behavioral Sciences (MindTap C...
Statistics
ISBN:9781305504912
Author:Frederick J Gravetter, Larry B. Wallnau
Publisher:Cengage Learning
Elementary Statistics: Picturing the World (7th E...
Statistics
ISBN:9780134683416
Author:Ron Larson, Betsy Farber
Publisher:PEARSON
The Basic Practice of Statistics
Statistics
ISBN:9781319042578
Author:David S. Moore, William I. Notz, Michael A. Fligner
Publisher:W. H. Freeman
Introduction to the Practice of Statistics
Statistics
ISBN:9781319013387
Author:David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:W. H. Freeman