Thursday, December 22, 2016

Confirmation Bias

This has been a different year. Even halfway through the year people were talking about how crazy 2016 is, and it hasn't disappointed. From the many celebrity deaths such as Gene Wilder, Prince, and Alan Rickman (many more, not a comprehensive list) to the Cubs winning the World Series to Donald Trump winning the presidency to snow in the Sahara Desert, it's been a wild ride.

I don't like doing year end reviews before the year is over, because crazy or amazing things can happen all the way through the 31st of December. Those who created their lists during the first half of December would have missed the last item I pointed out above - snowfall in the Sahara:

Crazy! Beautiful, but crazy! Of course taking it to social media, the crazy takes a different turn. Instead of just enjoying the crazy beauty of nature, it turns into a political discussion related to climate change. And of course everyone sees just what they want to see. Those more concerned with the environment point this out as an indicator of climate change, and those more concerned with government overreach point this out as an argument against global warming. I will say that from a scientific point of view, the idea that global warming could not lead to snow in a place that is usually hot is actually a little backwards. Theoretically, global warming can lead to more moisture in the air, which can lead to snow, so it's not just about the temperature itself, which is part of why the other side has started referring to it as climate change instead of global warming. That doesn't stop me from making jokes when it's 10 degrees outside about how much I'm looking forward to global warming.

The issue is that neither side is really supported by this isolated event. Whether or not climate change or global warming is a thing, snow in the Sahara does not make or break either case. A consistent pattern one way or the other would lead more toward something measurable, but it's a rare enough event that I don't think we have enough information. It also snowed in 1979:

And if you look around there are reports of possible snow in the Sahara in 2005 and 2012. Four times in over 40 years hardly a pattern makes for either side.

Rather, what we have is a clear pattern of confirmation bias. Confirmation bias is when a person has an idea they hold to be true, and any evidence they see is molded around their world view to help them confirm what they already believe to be true. One side thinks the snow proves man is changing the world's climate, and the other side thinks the snow proves that we are not.

This is what in statistics we would call an outlier. The problem with outliers is that sometimes we ignore them because they are such a strange occurrence that it ruins our simple model even though it's important to consider what would cause that extreme case. The other problem with outliers is that sometimes we focus too much attention on them and treat them as if they are regular cases instead of just abnormal phenomenon. Statistically speaking it probably should snow in the Sahara once every couple decades.

Confirmation bias is related to cognitive dissonance, which is the idea that when confronted with conflicting evidence contrary to our existing view, the tension must somehow be resolved by either dismissing the new evidence or by adjusting it (often subconsciously) to fit the previous belief. For example, I haven't said if I think climate change is a thing or not, but people with strong beliefs one way or the other will tend to have one of two responses to what I've written. They will either apply what I've written about how this doesn't prove anything just to the other side's argument if they believe what I'm saying or if they don't like what I'm saying they will read it as though I agree with the other side and say that I'm actually wrong about the weakness of the evidence.

Think through what I've written and by identifying how you react to my position that the snow doesn't mean as much as you think it means may help you understand where your own biases are positioned. Only by recognizing and understanding your own bias can you do anything about it.