Problem 5 True or False a) If the correlation coefficient 1 r= ± 1, then all the
ID: 2922220 • Letter: P
Question
Problem 5 True or False a) If the correlation coefficient 1 r= ± 1, then all the data points lie exactly on a straight line. T F b) The correlation coefficient r is a number that indicates the direction and the strength of the relationship between the dependent variable y and the independent variable x. c) If the correlation coefficient r=0, then there is no linear relationship whatsoever between the dependent variable y and the independent variable x d) The standard deviation is a measure of the linear relationship between two quantitative variablesTF e)The best fitting line relating the dependent variable y to the independent variable x, often called the regression or least-squares line, is found by minimizing the sum of the squared differences between the data points and the line itself. f) The scatterplot is a graph that is used to graphically represent the relationship between two quantitative variables TF g) If the linear relationship between the dependent and independent variables is positive, the scatterplot will show the data points on the (r, y) plane generally moving from the lower left corner to the upper right corner. T F h)If two variables have a correlation coefficient equal to 0.005, this means that there is no relationship between the two variables i) A perfect correlation between two variables will always produce a correlation coefficient of+1 TF T F T F TF T F Extra credit problem (extra 20% to Hwl, you should show calculations-numerical solution The summary statistics tor the number admitted and the number denied broken down by the gender are given in the following table: (University of California, Berkley) Admitted 3738 1494 4704 2827 Total 8442 4321 % Admitted 44 3% 346% Men Women These numbers strongly suggest bias against women However if the data are fuuther broken down by the major to which admission was sought then a completely different picture emerges. The following table gives the number of men and women who applied to the six largest majors (which account for over third of the total number of applicants) and the corresponding admission rates. Total No of Men Women Total men No of applicantsAdmitted 825 560 325 417 191 373 2691 Major No of applicants Admitted applicns Admitted 62 63 37 25 593 375 393 341 1835 68 34 35 24 585 918 792 67 35 34 25 28 714 4526 Total 30 39 How we can make a fair comparison between the admission rates of men and women? Explain.Explanation / Answer
We are allowed to do 4 subparts question at a time. Post again for more subparts of question.
5
a) True
A perfect correlation of ± 1 occurs only when the data points all lie exactly on a
straight line. If r = +1, the slope of this line is positive. If r = -1, the slope of this
line is negative.
b) True
The quantity r, called the linear correlation coefficient, measures the strength and
the direction of a linear relationship between two variables. The linear correlation
coefficient is sometimes referred to as the Pearson product moment correlation coefficient in
honor of its developer Karl Pearson.
c) True
d) False
No correlation: If there is no linear correlation or a weak linear correlation, r is
close to 0. A value near zero means that there is a random, nonlinear relationship
between the two variables
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.