Guessing the Probability Distribution

Tips for guessing what distribution a variable (or set of values) might have People often assume that the frequency with which a variable will take on different values (i.e., probability distribution) is likely to follow a bell curve (i.e., a normal distribution); this is often a mistake. Instead, consider these rules of thumb for deciding which probability distribution to use as a model in different situations: (1) Binomial - when flipping coins Number of occurrences out of a fixed nu...
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Correlation Coefficient as a Gateway to Skepticism

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The correlation coefficient as a gateway to radical skepticism:Suppose you calculate that two variables are moderately correlated. For instance, you find that self-reported happiness has a correlation r=0.32 with self-reported willpower, as I found in one of my studies. What are the possible explanations for (or causes of) this? A Causes B - Increasing A is a cause of increasing B but not the reverse. [e.g., more happiness causes more willpower] (2) B Causes A - Increasing B is a cause ...
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