The Number of Hours Seniors Work Per Week

1. The Number of Hours Seniors Work Per Week Adam Cannon Dan Franklin Shana Sicilia OmieLosinno

2. Method • We decided to survey random seniors throughout the day. • We surveyed for the number of hours spent working per week. Win

3. Hypothesis • We can be 95% confident that seniors spend about 12 hours a week working.

4. Data • 30 • 5 • 25 • 15 • 25 • 20 • 20 • 20 • 18 • 30 • 15 • 30 • 33 • 15 • 20 • 30 • 0 • 0 • 0 • 0 • 11 • 32 • 25 • 40 • 27 • 13 • 8 • 17 • 18 • 20 • 15 • 28 • 24 • 0 • 12 • 12 • 0 • 0 • 0 • 0 • 15 • 2 • 4 • 12 • 45 • .5 • 12 • 22 • 12 • 12 • 21 • 35 • 20 • 15 • 30 • 16 • 0 • 0 • 0 • 0 • 15 • 8 • 20 • 20 • 0 • 0 • 0 • 0 • 0 • 0 • 0 • 0 • 0 • 0 • 0 • 0 • 0 • 0 • 0 • 26

5. Summary Data • Total 958.5/80 • Sample Mean: 11.98 hrs/week • Sample Standard Deviation: 12.03 • Degrees of Freedom= 79 (75 on table)

6. T-score vs. Z-score • We decided to use a t-score because we did not survey a population, but rather a sample of a population to figure out the number of hours worked by seniors. Also, the population standard deviation is unknown.

7. 98% confidence level • Confidence level: 98% • Alpha level: 0.02 • T-score: 2.377 • Confidence Interval: 8.49<µ<14.89 • We can be 98% confident that the true mean number of hours worked by seniors per week is between 8.49 hours and 14.89 hours.

8. 90% confidence level • Confidence level: 90% • Alpha level: 0.10 • T-score: 1.665 • Confidence Interval: 9.74<µ<14.22 • We can be 90% confident that the true mean number of hours worked by seniors per week is between 9.74 hours and 14.22 hours.

9. 99% Confidence level • Confidence level: 99% • Alpha level: 0.01 • T-score: 2.643 • Confidence Interval: 8.43<µ<15.63 • We can be 99% confident that the true mean number of hours worked by seniors per week is between 8.43 hours and 15.63 hours.

10. 95% confidence level • Confidence level: 95% • Alpha level: 0.05 • T-score: 1.992 • Confidence Interval: 9.30<µ<14.66 • We can be 95% confident that the true mean number of hours worked by seniors per week is between 9.30 hours and 14.66 hours.

11. Which one? • We decided to use the 95% confidence level because it is the most commonly used. A 95% confidence level is larger than a 90%, but smaller than a 99%. We did not want it to be too large or too small.

12. Conclusion • Overall, we found that the averagenumber of hours worked by seniors during the week is 11.98 hours. • We found that the highest number of hours worked is 45 hours, and the least amount is .5 hours. There were also many people who did not have a job at all.