X2 High Wind Low Wind Output Force Insulator Type Oil Type 20.0 140 192 120 A 1
ID: 3251676 • Letter: X
Question
X2 High Wind Low Wind Output Force Insulator Type Oil Type 20.0 140 192 120 A 1 19.2 139 188 134 A 1 22.3 148 190 187 A 1 18.9 136 186 190 A 2 19.5 129 179 167 A 2 20.4 145 194 198 A 2 155 183 179 B 1 130 191 200 B 1 123 187 178 B 1 156 B 2 190 B 2 210 B 2 210 C 1 200 C 1 185 C 1 199 C 2 175 C 2 193 C 2 X2 High Wind Low Wind Output Force Insulator Type Oil Type 20.0 140 192 120 A 1 19.2 139 188 134 A 1 22.3 148 190 187 A 1 18.9 136 186 190 A 2 19.5 129 179 167 A 2 20.4 145 194 198 A 2 155 183 179 B 1 130 191 200 B 1 123 187 178 B 1 156 B 2 190 B 2 210 B 2 210 C 1 200 C 1 185 C 1 199 C 2 175 C 2 193 C 2 Problem 6: see Daraset with low new devices were ested under two weather conditions. wind speeds visibility and Low wind speeds with high visibility. Their accuracies are Device speed TLow wind speed High wind with high visibility with low visibility 39 48 136 45 55 10 87 Low wind speed with high visibility than at High wind speed with low visibility b) 11.5 points Find a 90% confidence interval for the difference for the means of the device accuracies. I1.5 pointsl What are the assumptions needed for the test in part (b).Explanation / Answer
(a)
Data:
n = n1 = n2 = 9
d-bar = 49.44444444
s (of d) = 10.41766662
Hypotheses:
Ho: d-bar 0
Ha: d-bar > 0
Decision Rule:
= 0.03
Degrees of freedom = 9 - 1 = 8
Critical t- score = 2.189154805
Reject Ho if t > 2.189154805
Test Statistic:
SE = s/n = 10.4176666186713/9 = 3.47255554
t = d-bar/SE = 49.4444444444444/3.47255553955709 = 14.23863316
p- value = 2.88346E-07
Decision (in terms of the hypotheses):
Since 14.23863316 > 2.189 we reject Ho and accept Ha
Conclusion (in terms of the problem):
There is sufficient evidence to support the claim.
(b)
n1 = n2 = n = 9
d-bar = 49.4444
s of d-bar = 10.4177
% = 90
Degrees of freedom = n - 1 = 8
SE = s/n = 3.472566667
t- score = 1.859548033
Width of the confidence interval = t * SE = 6.457404516
Lower limit of the confidence interval = d-bar - width = 42.98699548
Upper limit of the confidence interval = d-bar + width = 55.90180452
The 90% confidence interval is [42.99, 55.90]
(c) The samples are drawn from populations which are approximately normal.
Before After d = After - Before 140 192 52 139 188 49 148 190 42 136 186 50 129 179 50 145 194 49 155 183 28 130 191 61 123 187 64 d-bar = 49.44444444 s = 10.41766662Related Questions
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