Fundamentals of Statistics contains material of various lectures and courses of H. Lohninger on statistics, data analysis and here for more.

Exercise - Weight Loss of Coins

Suppose you have to solve the following problem. Some department of the mint wants to know whether their coins lose weight during usage over the years. They have therefore collected 114 coins of the same kind, but of different minting date, spanning a range of three decades. All of the coins are washed, dried, and weighed thereafter. The results are stored in file COINS

Your task is now

  • to decide if the weight of the coins decreases over time, and if so,
  • to give an estimate of the weight loss per year.
  • to compare the variance to the weight change?
  • Is the variance homoscedastic or heteroscedastic?

Go to the  DataLab  to investigate these questions.

Last Update: 2012-10-08