Transcript Steroids - eTutorHub

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Steroids
• To analyze if a baseball
player may have used
steroids in his career, you
decide to analyze his
homeruns during his first half
of his career and during final
half of his career.
Ho: μfirst half = μsecond half
Ha: μfirst half ≠ μsecond half
Player A
Player B
1st Half
2nd Half
1st Half
2nd Half
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39
0
33
14
38
11
44
8
43
21
25
8
47
27
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14
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47
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13
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43
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28
37
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48
0
39
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#1 Soda Shelf Life
• The shelf life of a soda is of
interest. Ten bottles are
randomly selected and
tested. Does the mean
shelf life exceed 120 days?
Shelf Life
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124
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106
115
138
163
159
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139
What if we know if the standard deviation is 10 days?
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#2 Injection Molding
10 seconds
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3
5
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6
5
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6
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20 seconds
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Housings of cell phones are
made with injection molding
and rated on a 1-10 scale
based on appearance. An
experiment was conducted
with either 10 second or 20
second cool-down times prior
to removal from mold -- does
this factor seem related to
appearance?
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#3 Home Shopping
• QVC wants to try out a “super-
shopper” program, where if you
spend enough money per day you
receive the “super-shopper”
designation. They want to know if
people start buying even more once
they receive this designation.
• The “not designated” data is for 10
people prior being named “supershoppers”
• The “designated” data is for the same
10 people after being named “super
shoppers”
Not
designated
($ spent/day)
Designated
($ spent/day)
65
73
81
89
57
65
66
74
82
90
82
90
67
75
59
62
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75
70
60
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#4 Opera Fund Raising
• An opera company has
tried three approaches to
solicit donations from 24
potential sponsors. The
24 sponsors were
randomly divided into
groups of 8 each, with
one approach being used
with each group. Do the
different approaches lead
to different $ amounts
committed?
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#5 Synthetic Vision I
• Three synthetic visions systems (SVS) for
pilots are tested for response time to
terrain-based obstacles. Each SVS is
tested on 10 independent pilots, for a total
of 30 pilots. Do the 3 SVS’s perform
differently?
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#6 Synthetic Vision II
• Three synthetic visions systems
(SVS) for pilots are tested. All three
SVS systems are used (in random
order) by each of the 100 pilots in
the study. Each pilot is then asked to
pick their favorite display. Is the
distribution of favorite picks the same
for male pilots as it is for female
pilots?
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Synthetic Vision PART III
• Three synthetic visions systems (SVS) for
pilots are tested for response time to
terrain-based obstacles. Each SVS is
tested on the same 10 pilots, with each
pilot seeing the SVS’s in a randomized
order. Do the 3 SVS’s perform differently?
[NOT PART OF CURRENT HOMEWORK]