MySpace |
18 |
18 |
20 |
30 |
35 |
118 |
119 |
123 |
149 |
160 |
167 |
200 |
200 |
200 |
208 |
209 |
300 |
300 |
306 |
400 |
400 |
500 |
546 |
MS 150 Statistics quiz nine • Name:
The table is the number of friends reported by MySpace users.
- _____________ Calculate the sample size n.
- _____________ Calculate the sample mean x.
- _____________ Calculate the sample standard deviation sx.
- _____________ Based on the data, what is the point estimate for the population mean μ?
- _____________ Calculate the standard error SE of the mean.
- _____________ Calculate the degrees of freedom n − 1.
- _____________ Calculate t-critical tc for a confidence level of 95%.
- _____________ Calculate the margin of error E for the mean.
-
p(__________ ≤ μ ≤ __________) = 0.95
Calculate the 95% confidence interval for the population mean.
- _____________
FaceBook reports that the average number of friends is 130.
Write out the null hypothesis that the population mean μ is 130 friends:
H0:
- Write out the alternate hypothesis that the population mean μ is NOT 130 friends:
H1:
Run a hypothesis test at a risk of a type I error alpha α = 0.05
- _____________ Calculate the value of the t-statistic t
- _________________________________ Do we reject or fail to reject the null hypothesis?
- _____________ Is the MySpace sample mean x statistically significantly different from the FaceBook population mean μ of 130 friends?