| Reviewed: |
Dec 05, 2010 by Statistics Editorial Board |
| Overview: |
This applet builds confidence intervals for the percentage of orange candies in box with two colors of candies. A smaller box visualizes the sample, and a graph keeps track of the location of the confidence interval. Students can take one sample (producing one CI) repeatedly, or take 100 random samples at once. The population percentage is hidden from view unless the student asks to see it, in which case it is displayed on the graph of confidence intervals. This allows the students to see whether each interval "hits" or "misses". Several parameters can be varied: sample size, confidence level and number of samples. A set of questions alongside the applet guides students. |
| Learning Goals: |
The applet helps students visualize the relationship between sample size, confidence level, and the width of a confidence interval. It also illustrates sampling variation and the idea that not all confidence intervals contain the population parameter. |
| Target Student Population: |
Introductory statistics |
| Prerequisite Knowledge or Skills: |
Students should have a prior exposure to confidence intervals, at least to the extent of understanding what an interval is, and understanding why they are used. Students should also understand the terms "population" and "sample." |
| Type of Material: |
Java applet |
| Recommended Uses: |
Students would easily work by themselves to answer the questions. No time is needed to "learn" how to use the applet. Recommended for in-class or out-of-class exploration of the topic. |
| Technical Requirements: |
Browser, Java |
