Survival of fruit flies on heat-treated mangoes

p = 637/5903 = 0.1079   survived the heat treatment

Use this diagram to explain that the distributions of the count of successes, proportion of successes and estimation error all have distributions with the same shape but different scaling.

(Note that the sample proportion, p, is used instead of the unknown π to draw the distributions and evaluate the se.)

Mention that the error distribution is particularly important — its standard deviation is the standard error.

We estimated that the probabilitiy of surviving the heat treatment is 0.1079. From the error distribution, it is unlikely that this estimate will be in error by more than 0.01.


The Queensland fruit fly, Bactrocera tryoni, can lay eggs in mangoes, so Australian mangoes must be treated before they can be exported to most international markets.

An experiment was conducted to determine the effectiveness of heat treatment of mangoes to kill fruit fly eggs. The table below shows the published results when mangoes containing 5,903 eggs were heat treated to a core temperature of 43 degrees Celsius.

Surviving adults 637
Eggs killed 5,266
Total eggs 5,903