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QUESTION 10 Studies suggest that there is a strong correlation between GPA and weekly hours spent...
Give an example of a lurking variable that might explain the nonsense correlation between time spent studying for an exam and grade received on the exam based on the scatterplot. Score on exam 100t Hours studying The lurking variable is "Current grade in the class." Students performing well in the class may not need to study long for exams. The lurking variable is "Study hours." The longer students study for the exam, the lower the grade they will receive on...
Is College GPA determined by a the number of hours /week a student studies, attendance, number of credits taken per semester or High School GPA? A sample of students was analyzed. The following initial regression output is shown below: 6. ssion Stotistics 810 0655 0530 0.580 Multiple R R Square usted R Square Standard Error 47023 17558 228100132 Regression Residual 16942 a3358 03430418191 00454 0 1565 interdept Hes Studied % a asses Attended Credits MS. GPA 2.2381 0 1009 00034...
Researchers examine the relationship between mother's education level and hours spent on homework each week for a random sample of 80 high school students. Students were grouped into four categories based on their mother's education level. Below are the summary statistics and graphs for the samples. Use this information to answer the next three questions. Responses: HomeWork Factors: MotherEdConsolidated Response statistics by factor MotherEdConsolidated MeanStd. Dev Std. Error 5.9 1.2 8.5 AA, trade, or some college 24 1.0 8.5 BA...
6. Two researchers are investigating the effects of time spent studying on the examination marks earned by students on a certain course. For a sample of 100 students, they have the examination mark, M, total hours spent studying, H, hours on primary study, P, and hours spent on revision. R. By definition, H = P+ R. The sarnple means of H. P. and R are 100 hours, 95 hours, and 5 hours, respectively. The sample correlation coefficients are 0.98 for...
6. Two researchers are investigating the effects of time spent studying on the examination marks earned by students on a certain course. For a sample of 100 students, they have the examination mark, M, total ours spent studying, H, on revision. R. By definition, H = P+ R. The sample means of H. P. and R are 100 hours, 95 hours, and 5 hours, respectively. The sample correlation coefficients are 0.98 for H and P, and 0.10 for H and...
43 college students 44% male, 56% female Students reported on the number of hours spent studying per week (0-40 hours), their life satisfaction (scale from 0-100), degree of stress they experienced over the last month (scale 0-5), and completed an IQ test (40-160). Students also reported their gender (1=male, 2=female) and cumulative GPA. For the statistical analysis performed, you need to provide responses to two questions: What type of statistical analysis was used to examine what kind of research question?...
43 college students 44% male, 56% female Students reported on the number of hours spent studying per week (0-40 hours), their life satisfaction (scale from 0-100), degree of stress they experienced over the last month (scale 0-5), and completed an IQ test (40-160). Students also reported their gender (1=male, 2=female) and cumulative GPA. For the statistical analysis performed, you need to provide responses to two questions: What type of statistical analysis was used to examine what kind of research question?...
QUESTION 27 Q27. A manager at a local bank analyzed the relationship between monthly salary (y, in $) and length of service (x, measured in months) for 30 employees. She estimates the model: Salary = Bo + B1 Service + ε. The following ANOVA table below shows a portion of the regression results. df SS M S F Regression 555,420 555,420 7.64 Residual 27 1,962,873 72,699 Total 28 2 ,518,293 Coefficients Standard Error t-stat p-value Intercept 784.92 322.25 2.44 0.02...
2. This week, we studied the test score Y versus number of hours, X, spent on test preparation, of a student in a French class of 10 students with the collected results shown below Number of hours studied Test score 31 10 14 73 37 12 60 91 21 84 17 (a) Use linear normal regression analysis method or the least-squares approximation method to predict the average test score of a student who studied 12 hours for the test (b)...
11. Suppose you are interested in estimating the effect of hours spent in an SAT preparation course (hours) on total SAT score (sat). The population is all college-bound high school seniors for a particular year. (i) Suppose you are given a grant to run a controlled experiment. Explain how you would structure the experiment in order to estimate the causal effect of hours on sat. (ii) Consider the more realistic case where students choose how much time to spend in...