Question

In: Statistics and Probability

Q4. Calculate the mean difference in scores (After - Before) and the sample variance of the difference.

ID After Before
1 1230 1074
2 1090 1039
3 1028 1004
4 1230 1154
5 1200 1144
6 1030 974
7 1220 1174
8 1085 1134
9 1000 1094
10 1320 1174
11 1075 1004
12 1040 1014
13 1030 1114
14 1110 1134
15 995 1079
16 1160 1184
17 1250 1254
18 1000 994
19 1110 1024
20 1045 1004
21 925 884
22 1005 1044
23 1150 1054
24 1015 1019
25 980 934
Q4. Calculate the mean difference in scores (After - Before) and the sample variance of the difference.
Mean Difference ==>
Sample Variance of Difference ==>
Q5. Calculate the LCL and UCL for a 90% CI (α = 0.1) for the mean difference in scores.
LCL ==>
UCL ==>
Based on this 90% interval, would you say the prep course improved scores (Yes/No)
Q6. Calculate the LCL and UCL for a 95% CI (α = 0.05) for the mean difference in scores.
LCL ==>
UCL ==>
Based on this 95% interval, would you say the prep course improved scores (Yes/No)

Solutions

Expert Solution

Number Before After Difference
1074 1230 -156 17234.4384
1039 1090 -51 690.6384
1004 1028 -24 0.5184
1154 1230 -76 2629.6384
1144 1200 -56 978.4384
974 1030 -56 978.4384
1174 1220 -46 452.8384
1134 1085 49 5434.6384
1094 1000 94 14094.4384
1174 1320 -146 14708.8384
1004 1075 -71 2141.8384
1014 1040 -26 1.6384
1114 1030 84 11820.0384
1134 1110 24 2373.6384
1079 995 84 11820.0384
1184 1160 24 2373.6384
1254 1250 4 824.8384
994 1000 -6 350.4384
1024 1110 -86 3755.2384
1004 1045 -41 265.0384
884 925 -41 265.0384
1044 1005 39 4060.2384
1054 1150 -96 5080.8384
1019 1015 4 824.8384
934 980 -46 452.8384
Total 26705 27323 -618 103613.04

Question 4




Question 5

Confidence Interval :-



Lower Limit =
Lower Limit = -47.2027
Upper Limit =
Upper Limit = -2.2373
90% Confidence interval is ( -47.2027 , -2.2373 )
Since CI values are in negative, we would say the prep course improved.

Question 6

Confidence Interval :-



Lower Limit =
Lower Limit = -51.8417
Upper Limit =
Upper Limit = 2.4017
95% Confidence interval is ( -51.8417 , 2.4017 )
Since CI contain 0, we would say the prep course does not improved.

orchestra answered 2 years ago
Next > < Previous

Related Solutions

How do I calculate variance for sample of different scores, estimated standard error for the mean...
How do I calculate variance for sample of different scores, estimated standard error for the mean difference and repeated measure T statistic
before the six sigma project, sample mean (hours)=45, sample variance= 34, sample size= 10. After the...
before the six sigma project, sample mean (hours)=45, sample variance= 34, sample size= 10. After the six sigma project, sample mean=32,sample variance =30. sample time between the populations is same or not with significance level 0f 5%. all of the following are true except? a. t value=5.14, p-value=0.000 b. t value is in rejection area c. 95% CI for difference around (7.67,18.35) d. All of the above choices are incorrect since we have to use wise t test since two...
A sample of scores is normally distributed with a mean equal to 27 and a variance...
A sample of scores is normally distributed with a mean equal to 27 and a variance equal to 16. What proportion is under 20
Calculate the sample mean and sample variance for the following frequency distribution of hourly wages for...
Calculate the sample mean and sample variance for the following frequency distribution of hourly wages for a sample of pharmacy assistants. If necessary, round to one more decimal place than the largest number of decimal places given in the data. Hourly Wages (in Dollars) Class Frequency 6.51 - 8.506.51 - 8.50 5050 8.51 - 10.508.51 - 10.50 1818 10.51 - 12.5010.51 - 12.50 4242 12.51 - 14.5012.51 - 14.50 2020 14.51 - 16.5014.51 - 16.50 4646 Copy Data Sample Mean:...
A. A sample of difference scores from a repeated-measures experiment has a mean difference of MD...
A. A sample of difference scores from a repeated-measures experiment has a mean difference of MD = 3 with an estimated standard error of sM = 1. If the sample size is n = 4, is this result sufficient to reject the null hypothesis, using a two-tailed test with alpha = .05? B. Hout, Duncan, and Sobel (1987) reported on the relative sexual satisfaction of heterosexual married couples. They asked each member of 91 couples to rate the degree to...
Is there a statistically significant difference in mean scores between any of the following groups? Calculate...
Is there a statistically significant difference in mean scores between any of the following groups? Calculate and report the mean for each group. If one or more mean differences exist, please identify the groups with significantly different means. Use the most appropriate statistical test to answer this question at the alpha = 0.05 level of significance. Identify the hypothesis statements, test statistic, p-value, and your decision. Group Score 1 12 1 15 1 18 1 24 1 25 1 21...
The variance of the scores on a skill evaluation test is 123,201 with a mean of...
The variance of the scores on a skill evaluation test is 123,201 with a mean of 1528 points. If 343 tests are sampled, what is the probability that the mean of the sample would differ from the population mean by greater than 29 points? Round your answer to four decimal places.
1. Which of these are random variables: Population mean, sample mean, population variance, sample variance, population...
1. Which of these are random variables: Population mean, sample mean, population variance, sample variance, population standard deviation, sample standard deviation, population range, sample range 2. Does variance matter? I have two routes to my work. Travel time on the first route takes me on average 20 minutes, and the second route 19 minutes. The standard deviation of travel time on the first route is 1.5 minutes, on the second is 5 minutes. Which route should I take?
This data is from a sample. Calculate the mean, standard deviation, and variance. x 38.3 35.2...
This data is from a sample. Calculate the mean, standard deviation, and variance. x 38.3 35.2 26.7 49.9 44.6 14.2 16.4 34 14.4 Please show the following answers to 2 decimal places. Sample Mean = Sample Standard Deviation = Sample Variance = Ooops - now you discover that the data was actually from a population! So now you must give the population standard deviation. Population Standard Deviation =
Hypothesis Test: Difference Between Means Sample A: 35 Observations, Mean = 10.255, Variance=0.310 Sample B :...
Hypothesis Test: Difference Between Means Sample A: 35 Observations, Mean = 10.255, Variance=0.310 Sample B : 20 Observations, Mean= 9.004, Variance= 0.831 H0: μA – μB= 0 H1: μA – μB ≠ 0 alpha=0.05 Can you run a hypothesis test for the difference between two means?
ADVERTISEMENT
Subjects
ADVERTISEMENT
Latest Questions
ADVERTISEMENT