The 1994 Summer Course for Teachers: CHANCE

 Written by Robert Hesse   

 Each summer, the Geometry Center hosts a two-week course for 
teachers.  This year's course, titled CHANCE, is a probability and 
statistics college class  taught by Laurie Snell at Dartmouth College.
Instead of teaching the theory  and then giving the students examples, 
Laurie has students read current news  items that involve probability 
and statistics and are asked questions  pertaining to the articles.  Some 
of the recent examples used in class were  whether major-league 
baseballs are juiced or not, the reliability of DNA  testing, and grade 
inflation at colleges over the past thirty years.  The goal  of this class is 
to "make students better able to make informed and critical judgements 
about news reports of chance issues that affect their daily lives." 
(CHANCE Pamphlet) Because the class topics depend on current events, 
there is no course outline.  CHANCE instructors also use perennially 
popular  issues such as polls, trials, and drug testing.

 In the summer course one morning, the CHANCE team (Peter Doyle, 
Laurie Snell,  Joan Garfield, Mark Foskey and Linda Green) had the 
participants read an  article about a study on the effects of taking daily 
supplements of vitamin E  or beta carotene or both.  Along with the 
article the participants were given  a question sheet.  They were asked to 
interpret a percentage the article  claimed, to use statistics to verify a 
claim, and to tell the instructors  whether they should continue taking 
doses of beta carotene and vitamin E.

 The students worked in groups of four or five discussing possible 
answers to  the solution.  After about twenty minutes of the discussion 
the instructors  called on the groups and had them respond to the 
questions.  Many of the  participants and the instructors went beyond the 
original questions and  debated different approaches to the problems.  

 In one of the more interesting discussions, the instructors compared a 
point  in the beta carotene article with the tossing of a fair coin.  The 
related  coin-tossing question was this:  What is the approximate 
probability of  getting 474 or more heads when a coin is tossed 876 
times?  Several of the  groups approached the problem differently.  The 
instructors showed a way of  answering the problem using a computer; 
they had a laptop run a thousand  simulations of flipping a fair coin 876 
times.  In those thousand  simulations, only four times did 474 or more 
heads appear.  They also used  statistical theory to show that such an 
incidence is unlikely.  The  combination of using technology (which 
gave one a strong feeling of what  was going on) along with statistical 
theory (which confirmed the feeling)  sparked interest in the material and 
aided in appreciating the power of  statistics  in everyday life. 

 The instructors approach to teaching probability was fast-paced and 
gripping.  Both the participants and the instructors were caught up in the 
discussion.   Although the participants were all practicing 
mathematicians, I believe that  this method can work for many students.  
Laurie believes that even if one  could not teach a class in this format the 
entire time, it would be a good  supplement to an already existing 
probability and statistics class.

 A second component to the summer CHANCE course is the use of 
computers.  Participants use programs to analyze data and run 
simulations.  They also  learn how to access and use the Internet system 
so that they could retrieve  articles and databases useful for projects.  
One of the more useful files  participants are able to access via Internet 
is the CHANCE database.  This  database contains articles from 
newspapers, raw data to use for projects, and  eventually some 
probability simulation programs.  For example besides  containing the 
newspaper articles used in the summer course, the database  contains 
statistics on the 1993 SAT scores.  There is also a BiWeekly chance  
newsletter that abstracts current news that involves statistical and  
probability concepts.  This newsletter can be obtained by e-mail by 
sending a  request to or can be read on the 
Chance Mosaic found  on the Geometry Center Mosaic 
( in their Online  Document Library.