Probability vs. Reality ~ by Ransom

People often conflate statistical distribution with probability.  They are different.  Statistical distribution shows what is being measured in a given sample set.  Probability describes the likelihood of events happening.  One shows what has happened, the other predicts what could happen.  Confusing the two results in a loss of information.

An egregious example of this confusion is firearm violence statistics, particularly related to the presence of firearms in the home.

The media will crow that the presence of firearms in the home increases the likelihood of being shot, especially in suicide.  The inevitable follow-up claim is that reducing firearm possession will therefore reduce firearm-related deaths.

These statements have several faults but the one error relevant to this article is the implicit assumption that gun-related violence occurs probabilistically.  It is as if invisible dice are being rolled in the backgrounds of our lives determining whether we shall get shot that day.  Getting shot isn't the result of a series of choices, no; the claim.  It just happens, and possessing firearms adds a hefty modifier to the roll.

Bull.

Events are not probabilistic.  Events are deterministic.

There is no true probability that a theorized event will happen.  It either will or it won't.  We assign probability to events as a work-around for our ignorance; events common enough to be treated as a commodity may be measured across a population using statistical analysis.

For such events it is possible to say that "such-and-such will happen this many times over a certain population in a given time period," but that is not because it simply happens at that frequency.  No; it happens because people make the decision to do it at a frequency consistent enough to be measured and compared.

Atomic and sub-atomic events are probabilistic.  Radioactive decay events are probabilistic.  Human decisions are deterministic.

Just because some human decisions can be discussed using probabilistic language does not change the underlying facts.

Beware language that divorces actions from actors.

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