Fixed effects

Commonlyidentified as the effects due to variables representing experimentalmanipulations (i.e., differences in outcomes under different experimentalconditions) or to variables representing stimulus, participant or higher-levelsampling unit attributes (i.e., differences in outcomes correlated with differentvalues of some attributes).  In practice, the distinction between random effectsand fixed effects is difficult to motivate consistently (Gelman & Hill,2007). Gelman, A.,& …

Fixed, free and equal parameters

In the estimation of any structural model, parameters can be 1. fixed at a known value (e.g., 0.0 ( 1/2 or 0.5), 2. free to take on a value based on the available data, or 3. required to be equal (or invariant) to any other parameter in the model.  See Structural equation modeling (SEM)

Fisher’s theory of evolutionary mimicry

A theory derived by Ronald A. Fisher (1890-1962) from two earlier theories, namely, Batesian mimicry as announced by Henry W. Bates (1825-1892) in 1861 and Müllerian mimicry published by Fritz Müller (1821-1897) in 1879.  The evolution of mimicry such that a unprotected organism (e.g., a caterpillar) acquires the colour or form of a unpalatable species …

Five factor model

A theory developed using factor analyses of ratings of the words people use to describe personality characteristics, stating that personality is composed of five primary associated dimensions (OCEAN): openness to experience, conscientiousness, extraversion, agreeableness and neuroticism.  Research findings on the five factors have revealed the following: they are dimensions, not types, with individuals varying continuously on them …

Fine motor abilities

Movements that require small subtle muscular coordination such as object manipulation, fastening buttons, and writing, typically coordinated with movements of the eyes and performed with the requisite postural control (e.g.,of  trunk muscles).  When applied to fingers and hands, it is usually referred to as manual dexterity.         See Direct corticomotoneuronal connections (or …