SandwichAnts: Ants on Sandwiches

Description Format Details Source


Ant counts on samples of different kinds of sandwiches


A dataset with 48 observations on the following 5 variables.

Trial Trial number
Bread Type of bread: Multigrain, Rye, White, or Wholemeal
Filling Type of filling: HamPickles, PeanutButter, or Vegemite
Butter Butter on the sandwich? no or yes
Ants Number of ants on the sandwich


As young students, Dominic Kelly and his friends enjoyed watching ants gather on pieces of sandwiches. Later, as a university student, Dominic decided to study this with a more formal experiment. He chose three types of sandwich fillings (vegemite, peanut butter, and ham & pickles), four types of bread (multigrain, rye, white, and wholemeal), and put butter on some of the sandwiches.
To conduct the experiment he randomly chose a sandwich, broke off a piece, and left it on the ground near an ant hill. After several minutes he placed a jar over the sandwich bit and counted the number of ants. He repeated the process, allowing time for ants to return to the hill after each trial, until he had two samples for each combination of the three factors.


Margaret Mackisack, “Favourite Experiments: An Addendum to What is the Use of Experiments Conducted by Statistics Students?", Journal of Statistics Education (1994)

statmanrobin/Stat2Data documentation built on Jan. 6, 2019, 1:08 a.m.