In: Statistics and Probability
Identify the null hypothesis, alternative hypothesis, test statistic, P-value, conclusion about the null hypothesis, and final conclusion that addresses the original claim. Use the P-value method.
Use the given data set of x and y values to answer the following questions. x-values 1 1 1 2 2 2 3 3 3 9 y-values 8 9 10 8 9 10 8 9 10 2
(a) Use StatCrunch to find the regression equation, ˆy = b0 + b1x and the sample correlation coefficient, r. Round all computations to three decimal places as needed.
(b) When α = 0.01, the critical values are −0.765 and 0.765. Is there a correlation between x and y?
(c) Find the best-predicted value y-value when x = 5. Round to the nearest tenth as needed.
The regression output is as follows
Null Hypothesis : There is no relation between x and y
Atlernate Hypothesis : There is correlation between x and y
F-test statistic from ANOVA table is 27.52739. UsuallyF-statistic is used for whole regression. but sometimes t-statistic of the x-variable is also taken which is -5.24665 here
p-value from ANOVa tabe is 0.000776984 (here we can also take the p-value fromx-variable which is same)
Since our p-value is less than alpha value of 0.05, we reject the null hypothesis
So the conclusion is there is correlation between x and y
Question (a)
The regression equation is = 10.677 + (-0.880) * x
Sample correlation coefficent r from the regression stastics multiple R = 0.880 rounded to 3 decimal places
Question (b)
Here the ciritcal values are −0.765 and 0.765. The t-test statistic of the x variable is -5.247 at = 0.01
The t-test statistic falls in the critical region because the critical region is from negative infinity to -0.765 and from 0.765 to positive infinity
So We reject the Null Hypothesis
Hence there is a correlation between x and y
Question (c)
The regression equation is = 10.677 + (-0.880) * x
= 10.677 + (-0.880) * 5
= 10.677 - 4.4
= 6.277
The besr predicted value of y = 6.3