A theoretical model where a growth process supposedly exists for two or more groups, but the identification of the persons in the groups is unknown or unmeasured (i.e., latent). The mixture analysis attempts to determine the optimal number of groups (G>1), isolate the growth parameters of the separate groups, and assign a probability of group …
Category Archives: Uncategorized
Growth
A term that has assumed a variety of meanings in the past. Simply put, it is an increase the size or mass of the developing organism. This is appositional growth or growth by accretion and which is distinguished from differential or allometric growth: changes in shape associated with increases or decreases in size. Starting with …
Group theory
A branchof mathematics that studies the properties of groups, which are algebraicstructures consisting of a set of elements and an operation that combines anytwo elements to form a third one. Group theory is a central feature of abstractalgebra, and finds applications in a wide variety of fields, includingphysics. Piaget believed that aschildren construct structures of …
Grooming
Care of the body surface, which can be individual or socially directed. See Dustbathing
Gross motor abilities
Movements involving large muscular coordination in which whole body posture and strength are often of primary importance as in, for example, climbing, jumping and walking. See Crawling, Cruising, Fine motor abilities, Fundamental movement patterns, Gait, Galloping, Hopping, Locomotion, Motor ability, Motor milestone, Posture, Skipping, Running, Walking
Greenhouse-Geisser epsilon
A correction factor that is smaller than 1 if the sphericity assumption in an ANOVA is violated. The factor is multiplied with F, making the test more conservative. It is a method of correcting the degrees of freedom of the within-subject F-tests in the analysis of variance of repeated measures or longitudinal data so as …
Gravitational field
The region of space in which one massive body (i.e., a body with mass) exerts a force of attraction on another massive body. The ratio of the force to the mass of the second body gives the strength of the gravitational field. See Center of gravity, Center of mass, Force, Inertia, Mass
Gray matter
Grayish nervous tissue in regions of the brain in which are found aggregations of unmyelinated neurons as well as fibers, and making up about 40% of the brain. This portion of the brain is divided into: 1. cortical gray matter, consisting of unmyelinated neurons, found at the surface of the brain, and 2. sub-cortical gray matter situated …
Grasp response
Flexing of the fingers or toes when a newborn’s palm of the hand (palmar grasp) or sole (plantar grasp) of the foot is stimulated (see first figure below). The power exerted by the healthy full term newborn performing the palmar grasp (also referred to as the palmar reflex) is evident in recordings made by John …
Grapheme
Letter units that may contain one or more letters, but that map to a single sound (e.g., k, ch). They not only include letters, but also Chinese ideograms, numerals, punctuation marks, and other symbols. A digraph contains two graphemes for one phoneme, and a triagraph three graphemes for one phoneme (e.g., itch in witch). See …