Question 1

A researcher wishes to test the hypothesis that there is a correlation between IQ and math ability. A random sample of 8 subjects was selected. Each subject was given an IQ test, and then rank-ordered in terms of mathematical ability. $$\begin{array} { c c } 
\text { IQ Score } & \text { Math Rank } \
130 & 1 \
92 & 5 \
115 & 4 \
115 & 3 \
82 & 6 \
82 & 7 \
60 & 8 \
120 & 2
\end{array}$$
-Should Ho be rejected or accepted? If rejected, state the level of significance.

Accepted Answer

The answer of A researcher wishes to test the hypothesis...

Question 2

The Following Questions will be based on the following: 
A group of 10 college seniors was randomly selected and given a WAIS-III IQ test. The IQs were recorded and then compared with each student's rank in class. The data are as follows: $$\begin{array} { l c c } 
\text { Student\# } & \text { IQ } & \text { Rank In Class } \
\text { 1. } & 120 & 1 \
\text { 2. } & 125 & 2 \
\text { 3. } & 122 & 3 \
\text { 4. } & 110 & 4 \
\text { 5. } & 95 & 5 \
\text { 6. } & 105 & 6 \
\text { 7. } & 100 & 7 \
8 . & 110 & 8 \
9 . & 100 & 9 \
10 . & 94 & 10
\end{array}$$
-Is the correlation significant?

Accepted Answer

The answer of The Following Questions will be based on...

Question 3

A researcher wishes to find out whether there is a dependable relationship between the severity of earthquakes and temperature for the 7 days immediately preceding the quake. A sample of 10 measured earthquakes was randomly selected from those recorded since 1965. For each area both the Richter value (higher value meaning more severe quakes) and the mean temperature for the 7 days preceding the quakes were recorded. The data follow: $$\begin{array} { l c l } 
\text { Area } & \text { Richter Scale Value } & \text { Mean Temperature } \
\text { A } & 8.0 & 65 \
\text { B } & 7.0 & 67 \
\text { C } & 4.9 & 70 \
\text { D } & 6.5 & 66 \
\text { E } & 5.0 & 65 \
\text { F } & 5.5 & 60 \
\text { G } & 5.0 & 63 \
\text { H } & 4.5 & 64 \
\text { I } & 5.0 & 65 \
\text { J } & 2.0 & 65
\end{array}$$ Neither distribution appears to be skewed.
-Should Ho be rejected or accepted?

Accepted Answer

The answer of A researcher wishes to find out whether...

Question 4

A researcher is interested in testing the hypothesis that income is negatively related to family size. A random sample of 10 families was selected from the population of a large mid-western city. All families were assessed on both their per-family income and their numbers of children $$\begin{array} { c c c } 
\text { Family } & \text { Per-family income } & \text { Number of children } \
\text { A } & \$ 190,000 & 2 \
\text { B } & \$ 30,000 & 6 \
\text { C } & \$ 19,000 & 7 \
\text { D } & \$ 40,000 & 3 \
\text { E } & \$ 23,000 & 6 \
\text { F } & \$ 40,000 & 4 \
\text { G } & \$ 25,000 & 5 \
\text { H } & \$ 40,000 & 3 \
\text { I } & \$ 28,000 & 1 \
\text { J } & \$ 30,000 & 5
\end{array}$$ Since the income distribution was badly skewed, it was decided not to use the Pearson r.
-Calculate the appropriate correlation

Accepted Answer

The answer of A researcher is interested in testing the...

Question 5

A researcher wishes to find out whether there is a dependable relationship between the severity of earthquakes and temperature for the 7 days immediately preceding the quake. A sample of 10 measured earthquakes was randomly selected from those recorded since 1965. For each area both the Richter value (higher value meaning more severe quakes) and the mean temperature for the 7 days preceding the quakes were recorded. The data follow: $$\begin{array} { l c l } 
\text { Area } & \text { Richter Scale Value } & \text { Mean Temperature } \
\text { A } & 8.0 & 65 \
\text { B } & 7.0 & 67 \
\text { C } & 4.9 & 70 \
\text { D } & 6.5 & 66 \
\text { E } & 5.0 & 65 \
\text { F } & 5.5 & 60 \
\text { G } & 5.0 & 63 \
\text { H } & 4.5 & 64 \
\text { I } & 5.0 & 65 \
\text { J } & 2.0 & 65
\end{array}$$ Neither distribution appears to be skewed.
-On the basis of your statistical decision, which error, Type 1 or Type 2 might you have committed?

Accepted Answer

The answer of A researcher wishes to find out whether...

Question 6

A researcher wishes to find out whether there is a dependable relationship between the severity of earthquakes and temperature for the 7 days immediately preceding the quake. A sample of 10 measured earthquakes was randomly selected from those recorded since 1965. For each area both the Richter value (higher value meaning more severe quakes) and the mean temperature for the 7 days preceding the quakes were recorded. The data follow: $$\begin{array} { l c l } 
\text { Area } & \text { Richter Scale Value } & \text { Mean Temperature } \
\text { A } & 8.0 & 65 \
\text { B } & 7.0 & 67 \
\text { C } & 4.9 & 70 \
\text { D } & 6.5 & 66 \
\text { E } & 5.0 & 65 \
\text { F } & 5.5 & 60 \
\text { G } & 5.0 & 63 \
\text { H } & 4.5 & 64 \
\text { I } & 5.0 & 65 \
\text { J } & 2.0 & 65
\end{array}$$ Neither distribution appears to be skewed.
-If rejected, state the level of significance.

Accepted Answer

The answer of A researcher wishes to find out whether...

Question 7

Should Ho be rejected or accepted?

Accepted Answer

The answer of Should Ho be rejected or accepted?...

Question 8

A researcher is interested in testing the hypothesis that income is negatively related to family size. A random sample of 10 families was selected from the population of a large mid-western city. All families were assessed on both their per-family income and their numbers of children $$\begin{array} { c c c } 
\text { Family } & \text { Per-family income } & \text { Number of children } \
\text { A } & \$ 190,000 & 2 \
\text { B } & \$ 30,000 & 6 \
\text { C } & \$ 19,000 & 7 \
\text { D } & \$ 40,000 & 3 \
\text { E } & \$ 23,000 & 6 \
\text { F } & \$ 40,000 & 4 \
\text { G } & \$ 25,000 & 5 \
\text { H } & \$ 40,000 & 3 \
\text { I } & \$ 28,000 & 1 \
\text { J } & \$ 30,000 & 5
\end{array}$$ Since the income distribution was badly skewed, it was decided not to use the Pearson r.
-Should Ho be rejected or accepted? If Ho is rejected, state the level of significance.

Accepted Answer

The answer of A researcher is interested in testing the...

Question 9

A researcher has computed two significant Pearson r values from independent random samples. Sample A, 60 subjects, produced an r of .98 and Sample B, 50 subjects, produced an r of .71. Do the two sample correlations represent a common population correlation?

Accepted Answer

The answer of A researcher has computed two significant Pearson...

Question 10

A researcher wishes to test the hypothesis that there is a correlation between IQ and math ability. A random sample of 8 subjects was selected. Each subject was given an IQ test, and then rank-ordered in terms of mathematical ability. $$\begin{array} { c c } 
\text { IQ Score } & \text { Math Rank } \
130 & 1 \
92 & 5 \
115 & 4 \
115 & 3 \
82 & 6 \
82 & 7 \
60 & 8 \
120 & 2
\end{array}$$
-Calculate the appropriate correlation.

Accepted Answer

The answer of A researcher wishes to test the hypothesis...

Question 11

Calculate the t ratio, and make a statistical decision at the .05 level for the following combinations of r and N.
a. r = .25 and N = 31
b. r = .25 and N = 62
c. r = .60 and N = 27
d. r = .70 and N = 15

Accepted Answer

The answer of Calculate the t ratio, and make a...

Question 12

Calculate the t ratio and make a statistical decision at the .05 level for the following combinations of r and N.
a. r = .18 and N = 122
b. r = .92 and N = 5
c. r = .45 and N = 12
d. r = .38 and N = 28

Accepted Answer

The answer of Calculate the t ratio and make a...

Question 13

The Following Questions will be based on the following: 
A group of 10 college seniors was randomly selected and given a WAIS-III IQ test. The IQs were recorded and then compared with each student's rank in class. The data are as follows: $$\begin{array} { l c c } 
\text { Student\# } & \text { IQ } & \text { Rank In Class } \
\text { 1. } & 120 & 1 \
\text { 2. } & 125 & 2 \
\text { 3. } & 122 & 3 \
\text { 4. } & 110 & 4 \
\text { 5. } & 95 & 5 \
\text { 6. } & 105 & 6 \
\text { 7. } & 100 & 7 \
8 . & 110 & 8 \
9 . & 100 & 9 \
10 . & 94 & 10
\end{array}$$
-What conclusions might you draw?

Accepted Answer

The answer of The Following Questions will be based on...

Question 14

A researcher wishes to find out whether there is a dependable relationship between the severity of earthquakes and temperature for the 7 days immediately preceding the quake. A sample of 10 measured earthquakes was randomly selected from those recorded since 1965. For each area both the Richter value (higher value meaning more severe quakes) and the mean temperature for the 7 days preceding the quakes were recorded. The data follow: $$\begin{array} { l c l } 
\text { Area } & \text { Richter Scale Value } & \text { Mean Temperature } \
\text { A } & 8.0 & 65 \
\text { B } & 7.0 & 67 \
\text { C } & 4.9 & 70 \
\text { D } & 6.5 & 66 \
\text { E } & 5.0 & 65 \
\text { F } & 5.5 & 60 \
\text { G } & 5.0 & 63 \
\text { H } & 4.5 & 64 \
\text { I } & 5.0 & 65 \
\text { J } & 2.0 & 65
\end{array}$$ Neither distribution appears to be skewed.
-On the basis of the above data, can the severity of earthquakes be predicted on the basis of previous temperature?

Accepted Answer

The answer of A researcher wishes to find out whether...

Question 15

A researcher wishes to find out whether there is a dependable relationship between the severity of earthquakes and temperature for the 7 days immediately preceding the quake. A sample of 10 measured earthquakes was randomly selected from those recorded since 1965. For each area both the Richter value (higher value meaning more severe quakes) and the mean temperature for the 7 days preceding the quakes were recorded. The data follow: $$\begin{array} { l c l } 
\text { Area } & \text { Richter Scale Value } & \text { Mean Temperature } \
\text { A } & 8.0 & 65 \
\text { B } & 7.0 & 67 \
\text { C } & 4.9 & 70 \
\text { D } & 6.5 & 66 \
\text { E } & 5.0 & 65 \
\text { F } & 5.5 & 60 \
\text { G } & 5.0 & 63 \
\text { H } & 4.5 & 64 \
\text { I } & 5.0 & 65 \
\text { J } & 2.0 & 65
\end{array}$$ Neither distribution appears to be skewed.
-Calculate the correlation.

Accepted Answer

The answer of A researcher wishes to find out whether...

Question 16

For the following ranks, calculate the Spearman r_s $\begin{array}{c} \begin{array}{l} \text { R1 } \ 4.0 \ 8.5 \ 6.0 \ 1.0 \ 2.5 \ 2.5 \ 6.0 \ 8.5 \ 6.0 \ 10.0 \end{array} \begin{array}{l} \mathrm{R} 2 \ 5 \ 4 \ 3 \ 1 \ 2 \ 6 \ 8 \ 7 \ 9 \ 10 \end{array} \end{array}$

Accepted Answer

The answer of For the following ranks, calculate the Spearman...

Question 17

For the following scores,
a. Find the Pearson r.
b. If Ho is rejected state the level of significance. X Y $$\begin{array} { c l } 
\mathrm { X } & \mathrm { Y } \
12 & 10 \
2 & 3 \
5 & 7 \
9 & 5 \
11 & 9 \
10 & 8 \
4 & 6 \
1 & 3
\end{array}$$

Accepted Answer

The answer of For the following scores,
a. Find the Pearson...

Question 18

If rejected, state the significance level.

Accepted Answer

The answer of If rejected, state the significance level....

Question 19

11-106.For the following ranks,
a. Calculate the Spearman r
b. Should Ho be rejected or accepted? If rejected, state the significance level. $\begin{array}{c}
\begin{array}{l}
\mathrm{R} \
2.5 \
2.5 \
1.0 \
5.5 \
7.0 \
8.0 \
4.0 \
5.5 
\end{array}
\begin{array}{l}
\mathrm{R} 2 \
1 \
2 \
5 \
7 \
8 \
6 \
4 \
3

\end{array}
\end{array}$

Accepted Answer

The answer of 11-106.For the following ranks,
a. Calculate the Spearman...

Question 20

A researcher wishes to find out whether there is a dependable relationship between the severity of earthquakes and temperature for the 7 days immediately preceding the quake. A sample of 10 measured earthquakes was randomly selected from those recorded since 1965. For each area both the Richter value (higher value meaning more severe quakes) and the mean temperature for the 7 days preceding the quakes were recorded. The data follow: $$\begin{array} { l c l } 
\text { Area } & \text { Richter Scale Value } & \text { Mean Temperature } \
\text { A } & 8.0 & 65 \
\text { B } & 7.0 & 67 \
\text { C } & 4.9 & 70 \
\text { D } & 6.5 & 66 \
\text { E } & 5.0 & 65 \
\text { F } & 5.5 & 60 \
\text { G } & 5.0 & 63 \
\text { H } & 4.5 & 64 \
\text { I } & 5.0 & 65 \
\text { J } & 2.0 & 65
\end{array}$$ Neither distribution appears to be skewed.
-How many degrees of freedom should be assigned?

Accepted Answer

The answer of A researcher wishes to find out whether...

Quiz 11: The Hypothesis of Association: Correlation

Should Ho be rejected or accepted?

A researcher has computed two significant Pearson r values from independent random samples. Sample A, 60 subjects, produced an r of .98 and Sample B, 50 subjects, produced an r of .71. Do the two sample correlations represent a common population correlation?

Calculate the t ratio, and make a statistical decision at the .05 level for the following combinations of r and N. a. r = .25 and N = 31 b. r = .25 and N = 62 c. r = .60 and N = 27 d. r = .70 and N = 15

Calculate the t ratio and make a statistical decision at the .05 level for the following combinations of r and N. a. r = .18 and N = 122 b. r = .92 and N = 5 c. r = .45 and N = 12 d. r = .38 and N = 28

For the following ranks, calculate the Spearman r_s $\begin{array}{c}\begin{array}{l}\text { R1 } \\4.0 \\8.5 \\6.0 \\1.0 \\2.5 \\2.5 \\6.0 \\8.5 \\6.0 \\10.0 \end{array}\begin{array}{l}\mathrm{R} 2 \\5 \\4 \\3 \\1 \\2 \\6 \\8 \\7 \\9 \\10\end{array}\end{array}$

For the following scores, a. Find the Pearson r. b. If Ho is rejected state the level of significance. X Y $\begin{array} { c l } \mathrm { X } & \mathrm { Y } \\12 & 10 \\2 & 3 \\5 & 7 \\9 & 5 \\11 & 9 \\10 & 8 \\4 & 6 \\1 & 3\end{array}$

If rejected, state the significance level.

Quiz 11: The Hypothesis of Association: Correlation

Should Ho be rejected or accepted?

A researcher has computed two significant Pearson r values from independent random samples. Sample A, 60 subjects, produced an r of .98 and Sample B, 50 subjects, produced an r of .71. Do the two sample correlations represent a common population correlation?

Calculate the t ratio, and make a statistical decision at the .05 level for the following combinations of r and N. a. r = .25 and N = 31 b. r = .25 and N = 62 c. r = .60 and N = 27 d. r = .70 and N = 15

Calculate the t ratio and make a statistical decision at the .05 level for the following combinations of r and N. a. r = .18 and N = 122 b. r = .92 and N = 5 c. r = .45 and N = 12 d. r = .38 and N = 28

For the following scores, a. Find the Pearson r. b. If Ho is rejected state the level of significance. X Y XY12102357951191084613\begin{array} { c l } \mathrm { X } & \mathrm { Y } \\12 & 10 \\2 & 3 \\5 & 7 \\9 & 5 \\11 & 9 \\10 & 8 \\4 & 6 \\1 & 3\end{array}X12259111041​Y103759863​

If rejected, state the significance level.

For the following scores, a. Find the Pearson r. b. If Ho is rejected state the level of significance. X Y $\begin{array} { c l } \mathrm { X } & \mathrm { Y } \\12 & 10 \\2 & 3 \\5 & 7 \\9 & 5 \\11 & 9 \\10 & 8 \\4 & 6 \\1 & 3\end{array}$