Category Archives: Blog Type

Which would you rather have?  A large sample that is biased, or a representative sample that is small?  The American Statistical Association committee that reviewed the 1948 Kinsey report on male sexual behavior, based on interviews with over 5000 men, left no doubt of their preference for the latter.  The statisticians –  William Cochran, FrederickContinue reading “Big Sample, Unreliable Result”

Companies now have a lot of data on their customers at an individual level.  Suppose you are tasked with forecasting customer spending at a grocery chain, and you want to understand how customer attributes, local economic factors, and store issues affect customer spending. You could design your study with hierarchical and mixed linear modeling methodsContinue reading “Mixed Models – When to Use”

In 2009, China began regional pilot programs that repurposed credit scores to a broader purpose – scoring a person’s “social credit.”  100 years earlier, at the height of the eugenics craze, the famous statistician Francis Galton undertook to repurpose statistical concepts in service of social engineering. The starting point was a social survey of LondonContinue reading “The Normal Share of Paupers”

The goal of any direct mail campaign, or other messaging effort, is to persuade somebody to do something.  In the business world, it is usually to buy something. In the political world, it is usually to vote for someone (or, if you think you know who they will vote for, to encourage them to actuallyContinue reading “UpLift and Persuasion”

Predicting the probability that something or someone will belong to a certain category (classification problems) is perhaps the oldest type of problem in analytics.  Consider the category “repays loan.” Equifax, the oldest of the agencies that provides credit scores, was founded in 1899 as the Retail Credit Company by two brothers, Cator and Guy Woolford. Continue reading “Lift and Persuasion”

Know those ads that follow you around the web, as a result of tracking cookies?  Many see them as an invasion of privacy, and EU rules made them subject to user consent.  Google recently announced that Chrome will eventually stop supporting these cookies.  A win for the consumer?  Perhaps, but there is another side toContinue reading “Ethical Dilemmas in Data Science”

What do stormy days, weekend evenings, and the last day of the month have in common?  They are all good times to negotiate a good price for a new car. Inclement days yield less customer traffic in auto showrooms, which is good for the buyer.  Weekend evenings, just before closing time, may make sales peopleContinue reading “Not Glamorous, But Lucrative”

“Do you have a bag?“ or “Would you like a bag?” have become common parts of the brick-and-mortar retail transaction.  Reusable bags, or simply doing without, have reduced the flow of plastic and paper into recycling.   E-commerce is a different matter.  I just unpacked a box of wine, and dealing with the protective spacers andContinue reading “Analytics Meets the Cardboard Box”