In: Statistics and Probability
The table below shows the arm spans (in inches) and the heights (in inches) of 10 randomly selected people.
Arm Span, x | 51 | 52 | 56 | 49 | 54 | 59 | 58 | 55 | 52 | 56 |
Height, y | 51 | 53 | 54 | 50 | 55 | 57 | 58 | 57 | 52 |
56 |
Perform a test, at the 5% level of significance, for the population slope β 1 of the regression line.
H0:
Ha:
t-Test Statistic (round this value to three decimal places) =
Critical t-Score (t α or t α / 2, use the t-distribution table to find, it should contain three decimal places) =
Conclusion (type R for reject H0, F for fail to reject H0):
The Regression Equation of Y on X is
Wher "r" = Correlation Coefficient
= Mean of X
= Mean of Y
= Standard Deviation of X
= Standard Deviation of Y
X | Y | |||||
51 | 51 | -3.2 | -3.3 | 10.24 | 10.89 | |
52 | 53 | -2.2 | -1.3 | 4.84 | 1.69 | |
56 | 54 | 1.8 | -0.3 | 3.24 | 0.09 | |
49 | 50 | -5.2 | -4.3 | 27.04 | 18.49 | |
54 | 55 | -0.2 | 0.7 | 0.04 | 0.49 | |
59 | 57 | 4.8 | 2.7 | 23.04 | 7.29 | |
58 | 58 | 3.8 | 3.7 | 14.44 | 13.69 | |
55 | 57 | 0.8 | 2.7 | 0.64 | 7.29 | |
52 | 52 | -2.2 | -2.3 | 4.84 | 5.29 | |
56 | 56 | 1.8 | 1.7 | 3.24 | 2.89 | |
TOTAL | 91.6000 | 68.1000 | ||||
MEAN | 54.2000 | 54.3000 | ||||
S.D | 3.0265 | 2.6096 | ||||
r | 0.9167 |
Therefore the Regression Equation of Y on X is
.
Therefore the fitted Regression Equation of Y on X is
Here 0.7904 is the slope of the Regression Equation of Y on X which is denoted by
Therefore
We frame the Null Hypothesis
:
To test the we use the t - Statistic
Therefore
Given α = 5% = 0.05
; So, we Reject at 5% Level of Significant
Therefore we conclude that
NOTE: The critical value of t has been extracted from the tabulated value of t; which posted below.