number of crimes (y) is affected by
unemployment (x1), number of police offcers (x2) and population (x3). 64 urban areas and found the following results.
Test at 5% significance levels if the coefficient of unemployment
Do not reject H0; p-value > alpha |
|
Reject H0; test statistics > t-table value or critical value |
|
Reject H0; p-value > alpha |
|
Do not Reject H0; p-value < alpha |
Solution:
Here, we have to check the significance of the coefficient of unemployment by using t test for regression coefficient. The null and alternative hypotheses are given as below:
Null hypothesis: H0: The coefficient of unemployment is not statistically significant.
Alternative hypothesis: Ha: The coefficient of unemployment is statistically significant.
We are given
Level of significance = α = 5% = 0.05
The test statistic is given as below:
t = β̂/SE
We have β̂ = 59.651, SE = 310.845, n = 64, df = n – 1 = 64 – 1 = 63
t = 59.651/310.845
t = 0.192
P-value = 0.848
(By using t-table)
[We already had given these values in the regression output.]
P-value > α = 0.05
So, we do not reject H0
Answer: Do not reject H0; p-value > alpha
There is insufficient evidence to conclude that the coefficient of unemployment is statistically significant.
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