# Data as a Second Language® Learn the Art of Data Science

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### Latest Data Science Terms

## Overmatching

A term applied to studies involving matching when the matching variable is strongly related to exposure but not to disease risk. Such

## Overfitted Models

Models that contain more unknown parameters than can be justified by the data.

## Overdispersion

The phenomenon that arises when empirical variance in the data exceeds the nominal variance under some assumed model. Most often encountered when

## Outside Observation

An observation falling outside the limits

## Outcomes Research

A multidisciplinary field of study that seeks to understand and improve the end results of particular health care practices and interventions.

## Orthogonal Polynomials

Two polynomials p i (x) and p j (x) of degree i and j respectively are said to be orthogonal if they

## Orthogonal Matrix

A square matrix that is such that multiplying the matrix by its transpose results in an identity matrix.

## Orthogonal

A term that occurs in several areas of statistics with different meanings in each case. Most commonly encountered in relation to two

## Orthant Probability

The probability that n random variables X1, X2, . . ., Xn are all positive when the n variates have a joint