In: Statistics and Probability
Listed below are amounts of court income and salaries paid to the town justices. All amounts are in thousands of dollars. Construct a scatterplot, find the value of the linear correlation coefficient r, and find the P-value using alphaequals0.05. Is there sufficient evidence to conclude that there is a linear correlation between court incomes and justice salaries? Based on the results, does it appear that justices might profit by levying larger fines?
Court Income 64.0 402.0 1567.0 1131.0 273.0 251.0 112.0 150.0 32.0 Justice Salary 31 45 92 58 48 60 26 27 19
What are the null and alternative hypotheses?
A.
Upper H 0H0:
rhoρequals=0
Upper H 1H1:
rhoρless than<0
B.
Upper H 0H0:
rhoρnot equals≠0
Upper H 1H1:
rhoρequals=0
C.
Upper H 0H0:
rhoρequals=0
Upper H 1H1:
rhoρnot equals≠0
D.
Upper H 0H0:
rhoρequals=0
Upper H 1H1:
rhoρgreater than>0
Construct a scatterplot. Choose the correct graph below.
A.
08001600050100Court IncomeJustice Salary
A scatterplot has a horizontal scale labeled “Court Income” from 0 to 1600 in intervals of 200 and a vertical scale labeled “Justice Salary” from 0 to 100 in intervals of 10. Nine points are plotted with approximate coordinates as follows: (260, 84); (420, 24); (640, 56); (760, 86); (880, 48); (900, 34); (1040, 86); (1260, 46); (1480, 18).
B.
08001600050100Court IncomeJustice Salary
A scatterplot has a horizontal scale labeled “Court Income” from 0 to 1600 in intervals of 200 and a vertical scale labeled “Justice Salary” from 0 to 100 in intervals of 10. Nine points are plotted with approximate coordinates as follows: (220, 84); (220, 80); (360, 80); (400, 70); (580, 84); (740, 58); (1080, 62); (1120, 30); (1420, 44).
C.
08001600050100Court IncomeJustice Salary
A scatterplot has a horizontal scale labeled “Court Income” from 0 to 1600 in intervals of 200 and a vertical scale labeled “Justice Salary” from 0 to 100 in intervals of 10. Nine points are plotted with approximate coordinates as follows: (40, 20); (60, 32); (120, 26); (160, 28); (260, 60); (280, 48); (400, 46); (1140, 58); (1560, 92).
D.
08001600050100Court IncomeJustice Salary
A scatterplot has a horizontal scale labeled “Court Income” from 0 to 1600 in intervals of 200 and a vertical scale labeled “Justice Salary” from 0 to 100 in intervals of 10. Nine points are plotted with approximate coordinates as follows: (140, 14); (140, 36); (340, 42); (660, 54); (740, 66); (900, 74); (1280, 90); (1320, 14); (1420, 74).The linear correlation coefficient r is
nothing.
(Round to three decimal places as needed.)
The test statistic t is
nothing.
(Round to three decimal places as needed.)
The P-value is
nothing.
(Round to three decimal places as needed.)
Because the P-value is
▼
less
greater
than the significance level
0.050.05,
there
▼
is not
is
sufficient evidence to support the claim that there is a linear correlation between court incomes and justice salaries for a significance level of
alphaαequals=0.050.05.
Based on the results, does it appear that justices might profit by levying larger fines?
A.
It appears that justices profit the same despite the amount of the fines.
B.
It does appear that justices might profit by levying larger fines.
C.
It does appear that justices might profit by issuing smaller fines.
D.
It does not appear that justices might profit by levying larger fines.
Click to select your answer(s).
null hypothesis: Ho: ρ | = | 0 |
Alternate Hypothesis: Ha: ρ | ≠ | 0 |
correlation coefficient r= | Sxy/(√Sxx*Syy) = | 0.875 |
test stat t= | r*(√(n-2)/(1-r2))= | 4.789 |
P value = | 0.002 |
Because the P-value is less than the significance level 0.05 there is sufficient evidence to support the claim that there is a linear correlation between court incomes and justice salaries
B)It does appear that justices might profit by levying larger fines.