CHAPTER III-3 ON TEACHING RESAMPLING AS A BASIC TOOL FOR EVERYDAY WORK THE PRO'S AND CON'S OF RESAMPLING 1) Does Resampling Produce Correct Estimates? If one does not make enough experimental trials with the resampling method, of course, the answer arrived at may not be sufficiently exact. For example, only ten experimental bridge hands might well produce far too high or too low an estimate of the probability of five or more spades. But a reasonably large number of experimental bridge hands should arrive at an answer which is close enough for any purpose. There are also some statistical situations in which resampling yields poorer estimates about the population than does the conventional parametric method -- usually "bootstrap" confidence-interval estimates made from small samples. But on the whole, resampling methods yield "unbiased" estimates, and not less often than do conventional methods. Perhaps most important, the user is more likely to arrive at sound answers with resampling because s/he can understand what s/he is doing, instead of grabbing the wrong formula in error. 2. Do Students Learn to Reach Sound Answers? In the 1970s, Kenneth Travers, who was responsible for secondary mathematics at the College of Education at the University of Illinois, and Simon organized systematic controlled experimental tests of the method. Carolyn Shevokas's thesis studied junior college students who had little aptitude for mathematics. She taught the resampling approach to two groups of students (one with and one without computer), and taught the conventional approach to a "control" group. She then tested the groups on problems that could be done either analytically or by resampling. Students taught with the resampling method were able to solve more than twice as many problems correctly as students who were taught the conventional approach. David Atkinson taught the resampling approach and the conventional approach to matched classes in general mathematics at a small college. The students who learned the resampling method did better on the final exam with questions about general statistical understanding. They also did much better solving actual problems, producing 73 percent more correct answers than the conventionally-taught control group. These experiments are strong evidence that students who learn the resampling method are able to solve problems better than are conventionally taught students. 3) Can Resampling Be Learned Rapidly? Students as young as junior high school, taught by a variety of instructors, and in languages other than English, have in the matter of six short hours learned how to handle problems that students taught conventionally do not learn until advanced university courses. In Simon's first university class, only a small fraction of total class time -- perhaps an eighth -- was devoted to the resampling method as compared to seven-eighths spent on the conventional method. Yet, the students learned to solve problems more correctly, and chose to solve more problems, with the resampling method than with the conventional method. This suggests that resampling is learned much faster than the conventional method. In the Shevokas and Atkinson experiments the same amount of time was devoted to both methods, but the resampling method achieved better results. In those experiments, learning with the resampling method was at least as fast as the conventional method, and probably considerably faster. 4. Is the Resampling Method Interesting and Enjoyable? Shevokas asked her groups of students for their opinions and attitudes about the section of the course devoted to statistics and probability. The attitudes of the students who learned the resampling method were far more positive -- they found the subject much more interesting and enjoyable -- than did the attitudes of the students taught with the standard method. And the attitudes of the resampling students toward mathematics in general improved during the weeks of instruction, whereas the attitudes of the students taught conventionally changed for the worse. Shevokas summed up the students' reactions as follows: "Students in the experimental (resampling) classes were much more enthusiastic during class hours than those in the control group, they responded more, made more suggestions, and seemed to be much more involved". Gideon Keren taught the resampling approach for just six hours to 14- and 15-year old high school students in Jerusalem. The students knew that they would not be tested on this material. Yet Keren reported that the students were very much interested. Between the second and third classes, two students asked to join the group even though it was their free period! And as the instructor, Keren enjoyed teaching this material because the students were enjoying themselves. Atkinson's resampling students had "more favorable opinions, and more favorable changes in opinions" about mathematics generally than the conventionally-taught students, according to an attitude questionnaire. And with respect to the study of statistics in particular, the resampling students had much more positive attitudes than did the conventionally-taught students. The experiments comparing the resampling method against conventional methods show that students enjoy learning statistics and probability this way. And they don't show the usual panic about this subject. This contrasts sharply with the less positive reactions of students learning by conventional methods, even when the same teachers teach both methods in the experiment. page # teachbk III-3day May 7, 1996