regression

regression, in psychology: see defense mechanism.

---

regression

In statistics, a process for determining a line or curve that best represents the general trend of a data set. Linear regression results in a line of best fit, for which the sum of the squares of the vertical distances between the proposed line and the points of the data set are minimized (see least squares method). Other types of regression may be based on higher-degree polynomial functions or exponential functions. A quadratic regression, for example, uses a quadratic function (second-degree polynomial function) to produce a parabola of best fit.

---

regression

1. Psychol the adoption by an adult or adolescent of behaviour more appropriate to a child, esp as a defence mechanism to avoid anxiety

2. Astronomy the slow movement around the ecliptic of the two points at which the moon's orbit intersects the ecliptic. One complete revolution occurs about every 19 years

3. Geology the retreat of the sea from the land

---

regression [ri′gresh·ən]

(geology)

The theory that some rivers have sources on the rainier sides of mountain ranges and gradually erode backward until the ranges are cut through.

(oceanography)

Retreat of the sea from land areas, and the consequent evidence of such withdrawal.

(psychology)

A mental state and a mode of adjustment to difficult and unpleasant situations, characterized by behavior of a type that had been satisfying and appropriate at an earlier stage of development but which no longer befits the age and social status of the individual.

(statistics)

Given two stochastically dependent random variables, regression functions measure the mean expectation of one relative to the other.

---

1.	(mathematics)	regression - A mathematical method where an empirical function is derived from a set of experimental data.
2.		regression - regression testing.