This JAVA applet assists the user in developing skills to classify a problem as one of the various types of confidence intervals, hypethesis tests and Chi Squared tests. This is not an easy application, but the comprehensive hints provided will improve the users skills in making such classifications.
Content Quality Concerns:
The only inference procedure for quantitative vs. quantiative relationships is "prediction interval for value of y given value of x" and for those cases the distinction between an confidence interval for the mean "y" vs. a prediction interval for an individual "y" is ignored - a substantial flaw. "Guidance" given for incorrect choices feels too mechanical at times. For example, an error for incorectly choosing for/against a chi-square test just gives a message that this is not/is a chi-square test. Similarily, the message for the regression interval just states whether there is or is no "value of x given here". When the "correct" choice is a test, the prompt given when a student chooses a CI is "You want to determine if something is true. Try again with a hypothesis test". Not a good message to send that hypothesis testing is finding out what is "true". Sometimes, the situations described are too terse. For example, one question says, "500 people were asked what is their favorite movie and who is their favorite author. Based on the data can you conclude that there is a relationship." The answer is chi-square for independence. I don't like this question as it is not clear at all how data would be collected so that someone could do a chi-square test. Are the movies/authors divided into categories? In my opinion, this question would only confuse students more, instead of helping them learn. Because of the vagueness of the wording on many questions, I would be hesitant to have students try these on their own at home. It might end up confusing them more and not helping them learn. If I can be there doing this stuff with the class, I can give hints or can clarify how the data would be collected to help them get to the right answer.
Content Quality Strengths:
This applet provides a good source of drill and practice for students in determining the appropriate statistical methods. This is often one of the most difficult things for students to learn. Students often master the particular procedures, but evaluating the sitaution and deciding which procedure is appropriate is much more difficult. One of the ways to help students learn to do this is simply practice. This applet is designed to give students the opportunity to practice, and it provides that experience. The situations to be examined are short and very easy to read. The variety of methods to be used gives students practice identifying different statistical techniques.
Ease of Use Concerns:
No record is kept of number of correct/incorrect choices, so it may be difficult for students to track their achievement level.
Ease of Use Strengths:
Very straightforward to use.
Potential Effectiveness Concerns:
This item is probably only effective near the end of a course when students have some familiarity with all of the procedures. It would be less effective if one or more of the inference procedures (e.g. prediction intervals in regression or chi-square goodness of fit) are not covered. The effectiveness of this tool would be greatly enhanced by adding the ability to limit the applet to only a few topics.
Potential Effectiveness Strengths:
This tool gives students access to practice something that is extremely difficult to learn. In addtion, it gives instructors a resource as these kind of questions take a long time to develop.
Potential Effectiveness Rating:
Source Code Available:
Source Code Available
Intended User Role:
Free for All