Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [fallacy]

25 questions
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What are common statistical sins?

I'm a grad student in psychology, and as I pursue more and more independent studies in statistics, I am increasingly amazed by the inadequacy of my formal training. Both personal and second hand experience suggests that the paucity of statistical…
Mike Lawrence
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Regression to the mean vs gambler's fallacy

On the one hand, I have the regression to the mean and on the other hand I have the gambler´s fallacy. Gambler’s fallacy is defined by Miller and Sanjurjo (2019) as “the mistaken belief that random sequences have a systematic tendency towards…
Luis P.
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Is there a name for the opposite of the gambler's fallacy?

The gambler's fallacy is a fallacy because of the assumed probability and the independence of the events. However, if, after flipping a coin 100 times and obtaining heads each time, I still believe the probability of obtaining tails to be 0.5, am I…
Igor F.
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Texas sharpshooter fallacy in exploratory data analysis

I was reading this article in Nature in which some fallacies are explained in the context of data analysis. I noticed that the Texas sharpshooter fallacy was particularly difficult to avoid: A cognitive trap that awaits during data analysis is…
Robert Smith
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War stories where wrong decisions were made based on statistical information?

I think it is fair to say statistics is an applied science so when averages and standard deviations are calculated it is because someone is looking to make some decisions based on those numbers. Part of being a good statistician then I would hope…
user2293
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The linearity of variance

I think the following two formulas are true: $$ \mathrm{Var}(aX)=a^2 \mathrm{Var}(X) $$ while a is a constant number $$ \mathrm{Var}(X + Y)=\mathrm{Var}(X)+\mathrm{Var}(Y) $$ if $X$, $Y$ are independent However, I am not sure what is wrong with the…
lanselibai
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Is there a formal name for this statistical fallacy?

"Given the infinite amount of possible configuration of the universe and the fact that if something in the universe were slightly different, we wouldn't exist, we can conclude that it couldn't (or probably could not) be created by the…
Vitor_figm
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What is it called when an experimenter discards results that are too unexpected?

There is a type of scientific error where an experimenter gets a result significantly different from prior researchers, assumes they made a mistake, and redoes the experiment until they get a more expected value, which they publish. I vaguely…
Ellen Spertus
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Why is the Likelihood function NOT a case of the inverse fallacy?

This may be a trivial question, but as a research psychologist I do not have a robust statistics background to answer it. It appears to me that the likelihood function--$L(\theta | \text{data}) = P(\text{data} | \theta)$--is committing the inverse…
ATJ
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Why is rejection of null hypothesis not a case of prosecutor's fallacy?

Here is what my understanding is: p-value - probability of finding the observed, or more extreme, results when the null hypothesis (H0) of a study question is true which is to say p-value$=P(evidence/nullhypothesis)$. Now when the p value is below a…
MiloMinderbinder
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Is there a word for believing events are independent when they are not?

This is sort of like the opposite of the gamblers fallacy, although it's not the "inverse gamblers fallacy". For instance, if I observe that in some condition, the expression of Gene A is elevated with p-value 1e-3, and the expression of Gene B is…
Jacob
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Statistical fallacy when not controlling for variables?

When someone says "You never see a Ferrari rust like a Honda", the logical flaw is that a Honda is typically used as daily drivers thru severe winters, while a Ferrari is a 2nd or 3rd car limited to sunny weekend use. Obviously, you must control…
JackOfAll
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What is wrong with Shiva Ayyadurai's statistical theory in this court filing?

Dr Shiva Ayyadurai ran in the Republican primary for Massachusetts senator in 2020, losing this race to Kevin O'Connor. He then filed a lawsuit alleging irregularities in the vote count. The suit is currently pending. His legal filing is embedded on…
Edwin Young
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Example of danger of ecological correlation of rates?

Lots of textbooks and websites warn about drawing conclusions from "ecological correlations" which are defined as correlations between rates or averages. All the places I've looked at have used the same 1970 Census example that shows how…
Joseph Garvin
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Is there a name for a fallacy, when a word is understood colloquially instead of technically?

I sometimes encounter a view that only perfect forecasting is really forecasting. For example, if I claim that I have a model which forecasts election results, people will think I'm making the absurd claim that I can forecast election results with…
user4945913
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