Post Hoc Conclusions

Post Hoc Conclusions

Our minds see a lot of patterns that don’t exist. We make observations of randomness and find patterns that we assume to be based on a causal link when in reality no causal structure exists between our observations. This can happen in 3 point shooting in basketball, in observations of bomb locations in WWII London, and in music streaming services. We are primed to see patterns and causes, and we can construct them even when we shouldn’t. One contributing factor for incorrect pattern observation is that we tend to make post hoc conclusions, making observations after the fact without predicting what we might expect to see before hand.

 

Using the WWII example, Cass Sunstein and Richard Thaler in the book Nudge show how people developed misconstructions of German bombing patterns in London during the war. The German bombing wasn’t precise, and there was no real pattern to the bombing raids and where bombs actually exploded across the city. Nevertheless, people mistakenly viewed a pattern in the random distribution of bombs. The authors describe the mistaken pattern identification by writing, “We often see patterns because we construct our informational tests only after looking at the evidence.”

 

People could map where bombs fell, and then create explanations for what targets the Germans were aiming at, for why the Germans would target a certain part of the city, and what strategic purpose the bombing was trying to accomplish. But these reasons are all post hoc constructions meant to satisfy a non-existent pattern that someone expected to find. We also see this in basketball, when a shooter makes a few baskets and is believed to have the hot hand or be on fire. In music streaming services, algorithms are actually tweaked to be less random, because listeners who hear two consecutive songs or more by the same band will assume the streaming isn’t randomizing the music, even though random chance will sometimes pick a string of songs from the same band or even from the same album.

 

The examples I mentioned in the previous paragraph are harmless cognitive errors stemming from poorly constructed post hoc explanations of phenomena.  However, post hoc conclusions based on non-existent patterns are important to consider because they can have real consequences in our lives and societies. If we are in a position to make important decisions for our families, our companies, or our communities, we should recognize that we possess the ability to be wildly wrong about observed patterns. It is important that we use better statistical techniques or listen to the experts who can honestly employ them to help us make decisions. We should not panic about meaningless stock market fluctuations and we should not incarcerate people based on poor crime statistic understandings. We should instead remember that our brains will look for patterns and find them even if they don’t actually exist. We should state assumptions before we make observations, rather than making post hoc conclusions on poor justifications for the patterns we want to see.

Crafting Stories

Our brains are awesome at pattern recognition. It helps us drive down the freeway and know when traffic is going to come to a stop, it helps us identify fresh bananas and avoid overly ripe ones, and it gives us the ability to do complex mathematics. The brain evolved to recognize and identify patterns in nature so that we could adapt and adjust to the world around us and live in societies with other people and their pattern recognizing brains.

 

Today however, our brains’ pattern recognition can get us in trouble. In our daily lives we encounter a lot of randomness. We have a lot of experiences and face a lot of situations that truly don’t have any meaning behind them, but just happened to happen. Whether it was our toast getting knocked off the counter, seeming to hit every red light on our way to work, or someone not texting us back, we have a lot of daily experiences that our brain will attempt to find patterns between to find meaning where there isn’t any (or at least isn’t any substantial meaning).  Being aware of our brain’s pattern recognition engine and its desire to create a story between random events is important if we want to be able to react to the world in a reasonable way and to draw reasonable conclusions about the world around us.

 

Ryan Holiday writes about the danger of creating unrealistic stories from the standpoint of our own egos in his book Ego is the Enemy. Holiday writes, “Crafting stories out of past events is a very human impulse. It’s also dangerous and untrue. Writing our own narrative leads to arrogance. It turns our life into a story – and turns us into caricatures…” Holiday was writing about the way we look at success in the lives of other people and the way we think about where we are going and how we have gotten to where we are today. We often see a clear path looking backward that really didn’t exist when the journey began. We likely fail to see the doubt, the uncertainty, and the luck that just happened to bounce along and open a new path for ourselves or someone else. We create a narrative that highlights our good decisions, downplays our errors, and makes our journey through life seem like an inevitable trajectory and not like a rocky forest path that just happened to wind up where it did and not someplace else.

 

Its likely that none of us will stop telling our life in the form of a story or that we will ever be able to turn our brain’s pattern recognition engine off to stop the stories, but we need to be aware of the fact that we do this. Our perceptions of the world will always be limited, which means the stories we tell will never truly represent the reality of the world around us. We also have strong incentives to tell a story that gives meaning to things without any meaning, like the person who cut us off on the freeway leading to the accident was clearly an immoral person who victimized me, the innocent and pure driver who didn’t deserve such misfortune. Our stories will also likely create positive groups that we belong to and out-groups that are somehow less virtuous than our group. Our stories will feature us as prime actors driving our life forward, when we know that sometimes we just bump into good fortune or receive an opportunity without truly doing anything to deserve the opportunity. Ultimately, our stories are likely to be tools to inflate our ego and our status, are likely to jumble together patterns that the brain perceived from nothing, and to include only slivers of reality from our singular perspective. The stories are not real, so we should question them and be aware of when we are trying to make decisions based on the story of our lives that we tell ourselves.