Wks 8, Chapter 7
____________, ____________: _______
Surname (e.g. “Straayer”), Given Name (e.g. “Dave”)
Class time
Here are percentage scores from Test 2 for the two sections of this class that I teach.
Let’s suppose this is a representative sample of all similar statistics classes.
39.1
69.6
76.5
87.8
1. mean score: ___________________
40.9
70.4
77.4
91.3
40.9
72.2
77.4
91.3
2. standard deviation: _______________
52.2
72.2
79.1
92.2
3. Standard error (st. dev. divided by
57.4
73
80.9
92.2
sqrt(samples size): ________________
60
73.9
81.7
92.2
64.3
74.8
84.3
93
The minimum score to get a “B-“ is 79.
65.2
74.8
85.2
93.9
66.1
74.8
87
94.8
67.8
75.7
87.8
96.5
Test the hypothesis that the average student on such tests earns a “B-“ or better. Use 0.05 as α.
97.4
97.4
100
100
105.2
107
108.7
109.6
111.3
113
Null hypothesis (using symbols): _______________________
Alternate hypothesis (also using symbols): ____________________
Test statistic (give the stastic name, like Z or T, and its value): __________________
P-value: _______________________
State your conclusion in words. Your sentence should not contain words like “stastic”, “hypothesis”,
“reject” or “not reject”. It should contain the P-value, (in parentheses) so that a reader who knows what
it is can see the justification for your conclusion.