In: Statistics and Probability
Consider the following regression results based on 20 observations. [You may find it useful to reference the t table.]
Coefficients | Standard Error | t Stat | p-value | |
Intercept | 31.4333 | 4.5131 | 6.965 | 0.000 |
x1 | 0.1987 | 0.1470 | 1.352 | 0.193 |
a-1. Choose the hypotheses to determine if the intercept differs from zero.
H0: β0 ≤ 0; HA: β0 > 0
H0: β0 ≥ 0; HA: β0 < 0
H0: β0 = 0; HA: β0 ≠ 0
a-2. At the 5% significance level, what is the
conclusion to the hypothesis test? Does the intercept differ from
zero?
Reject H0; the intercept is greater than zero.
Reject H0; the intercept differs from zero.
Do not reject H0; the intercept is greater than zero.
Do not reject H0; the intercept differs from zero.
b-1. Construct the 95% confidence interval for the slope coefficient. (Negative values should be indicated by a minus sign. Round "tα/2,df" value to 3 decimal places and final answers to 2 decimal places.)
b-2. At the 5% significance level, can we conclude the slope differs from zero?
Yes, since the interval contains zero.
Yes, since the interval does not contain zero.
No, since the interval contains zero.
No, since the interval does not contain zero.
A-1)
A-2)
P VALUE FOR INTERCEPT = 0.000
P VALUE < 0.05,REJECT Ho
...
b-1)
confidence interval for slope
n = 20
alpha,α = 0.05
estimated slope= 0.1987
std error = 0.147
Df = n-2 = 18
t critical value = 2.101 [excel function:
=t.inv.2t(α,df) ]
margin of error ,E = t*std error = 2.1009
* 0.147 =
0.3088
95% confidence interval is ß1 ± E
lower bound = estimated slope - margin of error =
0.1987 - 0.3088 =
-0.11
upper bound = estimated slope + margin of error =
0.1987 + 0.3088 =
0.51
CI (-0.11 , 0.51 )
b-2)
...............
Please revert back in case of any doubt.
Please upvote. Thanks in advance.