A random sample of eightyfive students in Chicago city high
A random sample of eighty-five students in Chicago city high schools takes a course designed to improve SAT scores. Based on these students, a 90% confidence interval for the mean improvement in SAT scores from this course for all Chicago city high school students is computed as (72.3, 91.4) points. The correct interpretation of this interval is
| that 90% of the students in the sample had their scores improve by between 72.3 and 91.4 points. | ||
| that 90% of the students in the population should have their scores improve by between 72.3 and 91.4 points. | ||
| Neither choice is correct. |
A random sample of eighty-five students in Chicago city high schools takes a course designed to improve SAT scores. Based on these students, a 90% confidence interval for the mean improvement in SAT scores from this course for all Chicago city high school students is computed as (72.3, 91.4) points. The correct interpretation of this interval is
| that 90% of the students in the sample had their scores improve by between 72.3 and 91.4 points. | ||
| that 90% of the students in the population should have their scores improve by between 72.3 and 91.4 points. | ||
| Neither choice is correct. |
A random sample of eighty-five students in Chicago city high schools takes a course designed to improve SAT scores. Based on these students, a 90% confidence interval for the mean improvement in SAT scores from this course for all Chicago city high school students is computed as (72.3, 91.4) points. The correct interpretation of this interval is
that 90% of the students in the sample had their scores improve by between 72.3 and 91.4 points.
that 90% of the students in the population should have their scores improve by between 72.3 and 91.4 points.
Neither choice is correct.
| that 90% of the students in the sample had their scores improve by between 72.3 and 91.4 points. | ||
| that 90% of the students in the population should have their scores improve by between 72.3 and 91.4 points. | ||
| Neither choice is correct. |
Solution
The correct answer is:
Neither choice is correct.
The correct interpretation is: We are 90% confident that true mean improvement in SAT scores from this course for all Chicago city high school students lies between 72.3 and 91.4 points. The confidence interval gives range of mean value for population, not for individual scores.
