ETC5521: Diving Deeply into Data Exploration

Making comparisons between groups and strata

Professor Di Cook

Department of Econometrics and Business Statistics

At the heart of quantitative reasoning is a single question: Compared to what?


-Edward Tufte

Making comparisons

  • Groups defined by strata labelled in categorical variables
  • Observations in strata, same or different?
  • Is there a baseline, or normal value?
  • What are the dependencies in the way the data was collected?
  • Are multiple samples recorded for the same individual, or recorded on different individuals?

How would you answer these questions?

  • Are housing prices increasing more in Sydney or Melbourne?
  • Is the quoted price of the unit/apartment I might buy reasonable, or is it too high?
  • Are you more at risk of MPox in Australia or Germany?
  • Is the Alfred or Epworth hospital better for giving birth?
  • It’s hot and dry today, is the risk of bushfires too high to go hiking?

Comparing strata

Case study: Melbourne’s daily maximum temperature (1/2)