“Why is Amazon trying to sell me an X? I just bought an X. Idiots!”
People who are compensated strictly based on their ability to predict the future, like poker players and marketers at e-commerce shops, tend to be much better at high school math than Twitter users.
People who are compensated strictly based on their ability to predict the future, like poker players and marketers at e-commerce shops, tend to be much better at high school math than Twitter users.
You need two insights here:
1) Conditional probability is a mathematical technology that does exist.
2) Buying X is not entirely random across the population.
The ways X is not random vary based on the good. Consider refrigerators.
1) Conditional probability is a mathematical technology that does exist.
2) Buying X is not entirely random across the population.
The ways X is not random vary based on the good. Consider refrigerators.
You probably buy one every ten years. If I don't know where you are in your refrigerator cycle, my prior estimate should be 2.7e-4 probability of you buying it tomorrow.
Suppose I know you bought yesterday. In my life on earth, I have realized that buyer's remorse is a thing.
Suppose I know you bought yesterday. In my life on earth, I have realized that buyer's remorse is a thing.
What's a SWAG for how often a purchase immediately goes wrong? Not right color? Fridge DOA? Shoot I mismeasured my kitchen? Wife just hates it? Call that 2%. If I fix it within a week, then 2% / 7 = 2.9e-3 probability of purchasing a new fridge.
That's a 10X relative risk.
That's a 10X relative risk.
Here's a true statement: People who will in 2018 give birth to a child named Abigail are at least 5X more likely to give birth to a child in 2019 than people chosen at random.
"Naming your child Abigail can't make you more likely to get pregnant."
Again, failure to do the math.
"Naming your child Abigail can't make you more likely to get pregnant."
Again, failure to do the math.
(You get a 2X there, for free, from the observation "If you had a child named Abigail this year you are biologically capable of having children; this is not true of no less than half of humanity. Now apply same insight to childbearing age and you're already at 5X+.)
