In: Statistics and Probability
|
"Hit" Group |
"Smashed Into" Group |
|
25 |
50 |
|
25 |
45 |
|
34 |
55 |
|
30 |
40 |
|
36 |
45 |
|
37 |
41 |
|
31 |
50 |
|
35 |
35 |
|
30 |
37 |
|
35 |
45 |
|
30 |
55 |
|
25 |
50 |
|
20 |
45 |
|
25 |
43 |
|
30 |
42 |
|
24 |
40 |
|
34 |
36 |
|
33 |
45 |
|
37 |
50 |
|
38 |
41 |
A. Null Hypothesis?
Ha: Smashed into group estimated higher speed than hit group
Ho: Smashed into group estimated lower or same speed than hit group(directional hypothesis)
B. Alternative hypothesis?
Ha: Smashed into group estimated higher speed than hit group
Ha: Smashed into group estimated lower or same speed than hit group
C. Risk Level?
.01
.5
.05
.25
D. What is the best statistical test to use?
correlation test
t-Test for dependent samples
t-Test for independent samples
z-test
E. Compute the test statistic.
A. Null Hypothesis?
Ho: Smashed into group estimated lower or same speed than hit group(directional hypothesis)
B. Alternative hypothesis?
Ha: Smashed into group estimated higher speed than hit group
C. Risk Level?
.05
D:
t-Test for independent samples
E:
Let sample 1: Hit group
Sample 2: "Smashed Into" Group
Following table shows the calculations for mean and sd for sample 1:
| X1 | (X1-mean)^2 | |
| 25 | 32.49 | |
| 25 | 32.49 | |
| 34 | 10.89 | |
| 30 | 0.49 | |
| 36 | 28.09 | |
| 37 | 39.69 | |
| 31 | 0.09 | |
| 35 | 18.49 | |
| 30 | 0.49 | |
| 35 | 18.49 | |
| 30 | 0.49 | |
| 25 | 32.49 | |
| 20 | 114.49 | |
| 25 | 32.49 | |
| 30 | 0.49 | |
| 24 | 44.89 | |
| 34 | 10.89 | |
| 33 | 5.29 | |
| 37 | 39.69 | |
| 38 | 53.29 | |
| Total | 614 | 516.2 |

Following table shows the calculations for mean and sd for sample 2:
| X2 | (X2-mean)^2 | |
| 50 | 30.25 | |
| 45 | 0.25 | |
| 55 | 110.25 | |
| 40 | 20.25 | |
| 45 | 0.25 | |
| 41 | 12.25 | |
| 50 | 30.25 | |
| 35 | 90.25 | |
| 37 | 56.25 | |
| 45 | 0.25 | |
| 55 | 110.25 | |
| 50 | 30.25 | |
| 45 | 0.25 | |
| 43 | 2.25 | |
| 42 | 6.25 | |
| 40 | 20.25 | |
| 36 | 72.25 | |
| 45 | 0.25 | |
| 50 | 30.25 | |
| 41 | 12.25 | |
| Total | 890 | 635 |

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