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Subjective Probability Estimation

Our different experiences provide us all with different ways of assessing probabilities that are not axiomatic. (Axiomatic probability tells us that a fair coin comes up heads half the time. It is theoretical and not based on our experiences.)  If I know someone from work then I will have a sense of how likely it is that they will complete a task they have volunteered for. Their partner and children will have different estimates of the likelihood based on their different experiences with them.  We don't often discuss this nor do we often quantify our probability assessments but living in a world with other people requires that we make them.

When someone tells me something happened that I deem (imperfectly, subjectively) to be unlikely I don't immediately believe them.  (Nor do I call them a liar to their face.)  I await evidence to shift my estimation.  If someone tells me that the sky is pink with green polka dots I will disbelieve them (and wonder what the joke is) to the point where I would not walk outside and look up with further justification.

The more unlikely an event is (to me, subjectively), then the more evidence is required for me to believe in its occurrence.

This is relevant in a political environment where lies are everyday occurrences. Yesterday Trump called Jeffrey Goldberg, the editor of the Atlantic (a magazine I have read for years) a slime journalist for being so rude as to mention that he was included in a group chat (on a private messaging app, Signal) about the planning for a military attack. My subjective estimation is that Goldberg has been a pretty good journalist for decades and that I would like to have some kind of evidence for attacking the person pointing out the idiocy of Trump's national security team. Is there evidence of Goldberg falsifying other reports? Bring it on.

Trump wearies me. He is vain and hungry for attention and the media I consume has featured him since the 80's.  The fact that he says outlandish things without any proof and so many people just nod their heads confuses and dismays me. (Am I the only one keeping score?)

He has spent his life telling outlandish lies, often directly contradicting in the afternoon what he said in the morning. Maybe yesterday he decided to be more honest.  I have my doubts.

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