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Calculates the logit (log-odds) and inverse-logit.

Usage

logit(mu)

inv_logit(eta)

Arguments

mu

A numeric object with probabilies, with values in the in the range \([0,1]\). Missing values (NAs) are allowed.

eta

A numeric object with log-odds values, with values in the range \([-\infty,\infty]\). Missing values (NAs) are allowed.

Value

A numeric object of the same type as mu and eta containing the logits or inverse logit of the input values. The logit and inverse transformation equates to

$$\text{logit}(\mu) = \log(\mu/(1-\mu))$$ $$\text{logit}^{-1}(\eta)= \exp(\eta)/(1 + \exp(\eta)).$$

Details

Values of mu equal to 0 or 1 will return \(-\infty\) or \(\infty\) respectively.

Examples

logit(0.2)
#> [1] -1.386294
inv_logit(-1.386)
#> [1] 0.2000471