Question

In: Statistics and Probability

Consider the following small data set. Subject x y 1 7 21 2 17 15 3...

Consider the following small data set.

Subject x y
1 7 21
2 17 15
3 15 24
4 5 19
5 14 30


Find the linear correlation coefficient.

?=

Given the following data set, let ? be the explanatory variable and ? be the response variable.

x 7 6 3 8 2 5 3
y 3 6 7 2 8 5 8

(a) If a least squares line was fitted to this data, what percentage of the variation in the ? would be explained by the regression line? (Enter your answer as a percent.)
ANSWER: %

(b) Compute the correlation coefficient: ?=

Solutions

Expert Solution

1)

correlation r='Sxy/(√Sxx*Syy) = 0.1061

(please take care of number of decimal places)

2)

a)

SST=Syy= 33.714286
SSE =Syy-(Sxy)2/Sxx= 3.708333
SSR =(Sxy)2/Sxx = 30.005952
Coefficient of determination R2=SSR/SST=0.8900

percentage of the variation in the ? would be explained by the regression line =89.0 %

b)

correlation r='Sxy/(√Sxx*Syy) = -0.9434

Related Solutions

443 Consider the data set: 8 4 3 6 17 15 13 7 21 11 32...
443 Consider the data set: 8 4 3 6 17 15 13 7 21 11 32 1 1. 1.What is the percentile rank of xi = 21? 2. What is the value corresponding to the 61th percentile, P61? 3. Find outliers, if exist.
Step 2 Data Set A x 1 2 3 4 5 6 7 y 7 7...
Step 2 Data Set A x 1 2 3 4 5 6 7 y 7 7 7 9 9 9 10 Data Set B x 1 2 3 4 5 6 7 8 9 10 11 y 4 6 6 6 8 9 9 9 10 10 10 Step 2 Find the equation for the least-squares line, and graph the line on the scatter plot. Find the sample correlation coefficient r and the coefficient of determination r2. Is r significant?...
Consider the following set of ordered pairs. x 5 2 2 3 7 6 y 3...
Consider the following set of ordered pairs. x 5 2 2 3 7 6 y 3 8 5 4 2 7 a. Using alphaequals0.10​, test for the significance of the regression slope. b. Construct a 90​% confidence interval for the population slope. a. Using alphaequals0.10​, test for the significance of the regression slope. Identify the null and alternative hypotheses. Upper H 0​: beta ▼ not equals less than greater than greater than or equals equals less than or equals nothing...
3. Consider the following data for two variables, x and y. x   2 3 4 5 7...
3. Consider the following data for two variables, x and y. x   2 3 4 5 7 7 7 8 9 y 4 5 4 6 4 6 9 5 11 a. Does there appear to be a linear relationship between x and y? Explain. b. Develop the estimated regression equation relating x and y. c. Plot the standardized residuals versus yˆ for the estimated regression equation developed in part (b). Do the model assumptions appear to be satisfied? Explain. d....
Consider the following data set. x 1 2 3 4 5 6 y 3.00 0.21 0.61...
Consider the following data set. x 1 2 3 4 5 6 y 3.00 0.21 0.61 0.70 1.13 1.17 a) plot the data (y versus x). Are there any points that appear to be outliers? If there are, circle them and label as such. b) produce a regression of y against x. Add the regression line to the plot in a). Do you think that the regression line captures the most important features of the data set reasonably well? c)...
Determine the​ vertex, focus, and directrix for the following parabola. A. y=4(x+2)^2-21 B. y-7=1/8(x-3)^2 C. x=1/4y^2
Determine the​ vertex, focus, and directrix for the following parabola. A. y=4(x+2)^2-21 B. y-7=1/8(x-3)^2 C. x=1/4y^2
A set of data has the following coordinates t 0 1 3 4 7 y 2...
A set of data has the following coordinates t 0 1 3 4 7 y 2 4 5 7 10 a) Find the least-squares fit to this data by a linear function of t (that is, find constants c1,c0 so that y(t) = c1t + c0 is the best linear fit to this set of data). b) Find the equation of the best quadratic fit to the same set of data. Then find the equation of the polynomial of smallest...
For the data set 1 2 3 4 7 7 7 8 11 12 12 15...
For the data set 1 2 3 4 7 7 7 8 11 12 12 15 15 16 17 17 17 18 20 20 22 24 24 25 26 26 26 26 27 30 32 32 33 34 34 36 38 39 43 44 45 46 47 47 48 51 52 52 53 54 54 54 55 56 58 58 59 61 63 65 65 67 69 70 73 75 75 76 77 77 79 80 81 82 82 (a)...
2. Consider the following data: x= 1, 2, 3, 4, 5 y =3, 2, 4, 6,...
2. Consider the following data: x= 1, 2, 3, 4, 5 y =3, 2, 4, 6, 5 By hand, not using Matlab, and showing your work: (a) Compute the correlation coefficient. (b) Find the least-squares line. (c) Find the standard deviation around the least-squares line.
For the following data set [ 1, 4, 3, 6, 2, 7, 18, 3, 7, 2,...
For the following data set [ 1, 4, 3, 6, 2, 7, 18, 3, 7, 2, 4, 3, 5, 3, 7] please compute the following 1. measures of central tendency (3 points) 2. standard deviation ( 5 points) 3. is 18 an outlier? (5 points) 4. describe the shape of the distribution (2 points)
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT