People love statistics. They let us understanding the world beyond our own senses. USA Today publishes a daily Snapshot which presents a graph of random statistics. Sports talk and business analysis are dominated by statistics. We measure our progress, or lack thereof, and compare ourselves with others, based on statistics about our size, activities and accomplishments.
A few days ago, I was looking at a regional planning document and saw something startling: an assertion that transit ridership in my region has been going down. Since transit ridership has been going up nationwide, I smelled a rat.
After digging around through a big pile of statistics, I realized that there are so many different ways of measuring transit ridership that one can easily prove either that ridership is going up or that ridership is going down. Some possible measurements include: