Infer Stats in Decision-Making
Over the past decade, ABC Manufacturing has increased the number of safety inspections per month in hopes to decrease the number accidents on their production line. Below is a list of how many inspections were conducted in a month and the corresponding number of accidents recorded. Is there a correlation, and has this leadership decision been effective?
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Inspections |
Accidents |
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20 |
181 |
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24 |
190 |
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28 |
167 |
|
40 |
160 |
|
60 |
120 |
|
64 |
124 |
|
64 |
118 |
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68 |
90 |
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70 |
94 |
|
72 |
85 |
A marketing team conducted a survey of 300 people to see if a person’s age affected their brand choice. People under the age of twenty-five made the following choices: Brand A (25), Brand B (42), Brand C (33). People over 65 made the following selections: Brand A (20), Brand B (38), Brand C (42). The group between those ages made these choices: Brand A (44), Brand B(40), Brand C (16). Form your hypotheses, run the appropriate test, and provide a conclusion to the marketing team.
Two schedules for giving rest were compared—the massed schedule and the spaced schedule. Twenty observations of the spaced schedule produced a mean of 26 errors. On the massed schedule 14 observations resulted in a mean of 36 errors. An α level of .05 was adopted and an F = 4.21 was obtained. What conclusion is appropriate?
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· spaced practice produces fewer errors than massed practice. |
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· none of the choices are correct |
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· the null hypothesis should be retained |
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· massed practice produces fewer errors than spaced practice |
With an acknowledgment to Sesame Street, "Which of these things is not like the others, which of these things doesn't belong?"
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· matched pairs |
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· independent samples |
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· natural pairs |
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· repeated measures |