In: Statistics and Probability
You may need to use the appropriate technology to answer this question.
Consider the following data on price ($) and the overall score for six stereo headphones tested by a certain magazine. The overall score is based on sound quality and effectiveness of ambient noise reduction. Scores range from 0 (lowest) to 100 (highest).
| Brand | Price ($) | Score | 
|---|---|---|
| A | 180 | 74 | 
| B | 150 | 71 | 
| C | 95 | 59 | 
| D | 70 | 56 | 
| E | 70 | 40 | 
| F | 35 | 24 | 
(a)
The estimated regression equation for this data is
ŷ = 22.328 + 0.317x,
where x = price ($) and y = overall score. Does the t test indicate a significant relationship between price and the overall score? Use α = 0.05.
State the null and alternative hypotheses.
H0: β1 = 0
Ha: β1 ≠
0H0: β1 ≥ 0
Ha: β1 <
0    H0:
β0 ≠ 0
Ha: β0 =
0H0: β0 = 0
Ha: β0 ≠
0H0: β1 ≠ 0
Ha: β1 = 0
Find the value of the test statistic. (Round your answer to three decimal places.)
Find the p-value. (Round your answer to four decimal places.)
p-value =
What is your conclusion?
Do not reject H0. We conclude that the relationship between price ($) and overall score is significant.Reject H0. We conclude that the relationship between price ($) and overall score is significant. Do not reject H0. We cannot conclude that the relationship between price ($) and overall score is significant.Reject H0. We cannot conclude that the relationship between price ($) and overall score is significant.
(b)
Test for a significant relationship using the F test. Use α = 0.05.
State the null and alternative hypotheses.
H0: β1 = 0
Ha: β1 ≠
0H0: β1 ≠ 0
Ha: β1 =
0    H0:
β1 ≥ 0
Ha: β1 <
0H0: β0 ≠ 0
Ha: β0 =
0H0: β0 = 0
Ha: β0 ≠ 0
Find the value of the test statistic. (Round your answer to two decimal places.)
Find the p-value. (Round your answer to three decimal places.)
p-value =
What is your conclusion?
Do not reject H0. We cannot conclude that the relationship between price ($) and overall score is significant.Do not reject H0. We conclude that the relationship between price ($) and overall score is significant. Reject H0. We conclude that the relationship between price ($) and overall score is significant.Reject H0. We cannot conclude that the relationship between price ($) and overall score is significant.
(c)
Show the ANOVA table for these data. (Round your p-value to three decimal places and all other values to two decimal places.)
| Source of Variation  | 
Sum of Squares  | 
Degrees of Freedom  | 
Mean Square  | 
F | p-value | 
|---|---|---|---|---|---|
| Regression | |||||
| Error | |||||
| Total | 

| SSE =Syy-(Sxy)2/Sxx= | 314.3194 | |
| s2 =SSE/(n-2)= | 78.5798 | |
| std error σ = | =se =√s2= | 8.8645 | 
| estimated std error of slope =se(β1) =s/√Sxx= | 0.0725 | ||
a)
H0: β0 = 0
Ha: β0 ≠ 0
| test stat t = | (bo-β1)/se(β1)= | = | 4.369 | 
| p value: | = | 0.0120 | 
Reject H0. We conclude that the relationship between price ($) and overall score is significant
b)
H0: β1 = 0
Ha: β1 ≠ 0
value of the test statistic =19.08
p value =0.012
Reject H0. We conclude that the relationship between price ($) and overall score is significant.
c)
| Source | SS | df | MS | F | p value | 
| regression | 1499.68 | 1 | 1499.68 | 19.08 | 0.012 | 
| Residual error | 314.32 | 4 | 78.58 | ||
| Total | 1814.00 | 5 |