Algebra skeptics, climate skeptics

(written by lawrence krubner, however indented passages are often quotes). You can contact lawrence at:, or follow me on Twitter.

You’ve probably already heard this one, but imagine you are invited to a game show where there are 3 large curtains, and a prize behind one of the curtains. You get to keep the prize if you guess the right curtain. You make a guess. Then the showrunner lifts one of the other curtains, revealing that there is no prize behind that other curtain. Now you are given a chance to change your mind, if you wish. Should you change your guess? Yes, because you had a 33% chance of being right before, but now you have a 50% chance of being correct.

This is deeply counter-intuitive, and even a very great mathematician, Paul Erdős, refused to believe this was true until he was shown simulations where this worked out as a reality. So even great mathematicians will sometimes have trouble grasping statistical inferences.

Climate change denialists take advantage of this fact. They point to raw data that shows the world is cooling, rather than warming. It takes fairly complicated adjustments of raw data to show the actual trend. Every adjustment is something denialists can use to argue that the results are being manipulated to achieve a “politically correct” result. It’s important to teach children about all aspects of this, both the value of raw, unadjusted data, but also the reason why adjustments are important to make.

In the USA, the weather service was building stations in Georgia by the late 1800s, but most weather stations in Alaska didn’t open till the oil pipeline was built in the 1980s. So if you look at the raw data, you are basically comparing the transition from Georgia to Alaska, so of course the raw data shows a cooling trend. You need to weed out the historical bias before you can se the actual trend, which is warming.