In: Statistics and Probability
Chapter 9, Section 1, Exercise 006
Computer output for fitting a simple linear model is given
below. State the value of the sample slope for this model and give
the null and alternative hypotheses for testing if the slope in the
population is different from zero. Identify the p-value and use it
(and a 5% significance level) to make a clear conclusion about the
effectiveness of the model.
The regression equation is Y=83.2-0.0133X.
Predictor | Coef | SE Coef | T | P |
---|---|---|---|---|
Constant | 83.23 | 11.94 | 6.97 | 0.000 |
X | -0.01327 | 0.01106 | -1.20 | 0.245 |
Sample slope:
p-value:
As per the given information,
The regression equation is Y=83.23 - 0.0133X.
Predictor |
Coef |
SE Coef |
T |
P |
||
Constant |
83.23 |
11.94 |
6.97 |
0.000 |
||
X |
-0.01327 |
0.01106 |
-1.20 |
0.245 |
The significance level is 0.05.
Sample slope: - From the above output, the slope coefficient is –
0.01327 which is approximately equals to - 0.0133.
The researcher wants to test if the slope in the population is different from zerot.
The null and the alternative hypothesis is,
p-value: From the above output, the p-value is 0.245.
Since the p-value (0.245) is greater than the significance level 0.05, so the researcher rejects the null hypothesis.
Therefore, it can be concluded that there is not sufficient evidence to support that the slope in the population is different from zero. Thus, the result of the study is statistically insignificant; that is, the model is not statistically effective.