In: Statistics and Probability
A group of 10 students who wish to enter a university achieve the following scores:
25, 17 , 29 , 29, 26, 24 , 23 , 26 , 24 , 33
...Construct a confidence interval for the proportion of students scoring 26 points or less.
...construct a 90% confidence interval for the average score of all students
using excel>Addin>phstat>confidence interval
we have
Confidence Interval Estimate for the Proportion | |
Data | |
Sample Size | 10 |
Number of Successes | 6 |
Confidence Level | 90% |
Intermediate Calculations | |
Sample Proportion | 0.6 |
Z Value | -1.64485363 |
Standard Error of the Proportion | 0.154919334 |
Interval Half Width | 0.254819628 |
Confidence Interval | |
Interval Lower Limit | 0.345180372 |
Interval Upper Limit | 0.854819628 |
a 90 % confidence interval for the proportion of students scoring 26 points or less is ( 0.3452 ,0.8548)
using excel>addin>phstat>confidence interval
we have
Confidence Interval Estimate for the Mean | |
Data | |
Sample Standard Deviation | 14.37590577 |
Sample Mean | 31 |
Sample Size | 10 |
Confidence Level | 90% |
Intermediate Calculations | |
Standard Error of the Mean | 4.546060566 |
Degrees of Freedom | 9 |
t Value | 1.833112933 |
Interval Half Width | 8.333442416 |
Confidence Interval | |
Interval Lower Limit | 22.67 |
Interval Upper Limit | 39.33 |
a 90% confidence interval for the average score of all students (22.67,39.33)