-The following R program was designed to (mostly) randomly select
-students to call for questions in a class room environment. It was
-created in Harvard Graduate School of Graduate Education's S-290 to
-replace a physical ping-pong ball jar.
+The following R program was designed to (somewhat) randomly select students
+to call for questions in a class room environment. It was created in Harvard
+Graduate School of Graduate Education's S-290 to replace a physical ping-pong
+ball jar.
It takes a list of options (e.g., students), selects one at random and
-returns it, and then adjusts the weights so that the selected option
-is relatively less likely to be selected in subsequent draws. Every
-student can be called on at any time.
+returns it, and then adjusts the weights so that the selected option is
+relatively less likely to be selected in subsequent draws. Every student can
+be called on at any time.
-It is particularly well suited to classes in which a reasonably small
-number of students will be called on a small number of times. Over
-even a small number of classes, a very balanced list is likely.
+It is particularly well suited to classes in which a reasonably small number
+of students will be called on a small number of times. Over even a small
+number of classes, a very balanced list is likely.
The software was written by Benjamin Mako Hill <mako@atdot.cc> and is
released into the public domain.
The first time you the program this you'll need to:
- Modify ping_pong_ball_jar.R in a text editor to include the list of
- options or students that you want. There are comments in the file
- which should help provide some direction.
+ Modify ping_pong_ball_jar.R in a text editor to include the list of options
+ or students that you want. There are comments in the file which should help
+ provide some direction.
Save the modified version for later if you'll be doing this again.
Type "get.ping.pong.ball()" and then <ENTER> within R.
- As a shortcut, you can usually just type <UP> once or twice to see
- the last command if you're going to be running it repeatedly.
+ As a shortcut, you can usually just type <UP> once or twice to see the last
+ command if you're going to be running it repeatedly.
Files
---------
ping_pong_ball_jar.R
- Contains the R necessary to run the program. You'll need to at least
- modify the list of options.
+ Contains the R necessary to run the program. You'll need to at least modify
+ the list of options.
ping_pong_ball_jar_simulation.R
simulation_unweighted_random.png
simulation_weighted.png
- Code and output from simulations that show the number of questions
- asked to each participant in a large number of simulated classes.
+ Code and output from simulations that show the number of questions asked to
+ each participant in a large number of simulated classes.