derived function derivative differential coefficient differential first derivative | the result of mathematical differentiation, the instantaneous change of one quantity relative to another, df(x) dx |
multiple regression multiple correlation | a statistical technique that predicts values of one variable on the basis of two or more other variables |
regression coefficient | when the regression line is linear (y axb) the regression coefficient is the constant (a) that represents the rate of change of one variable (y) as a function of changes in the other (x), it is the slope of the regression line |
correlation matrix | a matrix giving the correlations between all pairs of data sets |
correlation table | a two-way tabulation of the relations between correlates, row headings are the scores on one variable and column headings are the scores on the second variables and a cell shows how many times the score on that row was associated with the score in that column |
correlation correlational statistics | a statistical relation between two or more variables such that systematic changes in the value of one variable are accompanied by systematic changes in the other |
curvilinear correlation nonlinear correlation skew correlation | any correlation in which the rates of change of the variables is not constant |
partial correlation | a correlation between two variables when the effects of one or more related variables are removed |
first-order correlation | a partial correlation in which the effects of only one variable are removed (held constant) |
correlation coefficient coefficient of correlation correlation | a statistic representing how closely two variables co-vary, it can vary from - (perfect negative correlation) through (no correlation) to(perfect positive correlation), what is the correlation between those two variables? |
positive correlation direct correlation | a correlation in which large values of one variable are associated with large values of the other and small with small, the correlation coefficient is between and |
negative correlation indirect correlation | a correlation in which large values of one variable are associated with small values of the other, the correlation coefficient is between and - |
product-moment correlation coefficient Pearson product-moment correlation coefficient | the most commonly used method of computing a correlation coefficient between variables that are linearly related |
multiple correlation coefficient | an estimate of the combined influence of two or more variables on the observed (dependent) variable |
biserial correlation coefficient biserial correlation | a correlation coefficient in which one variable is many-valued and the other is dichotomous |
rank-order correlation coefficient rank-order correlation rank-difference correlation coefficient rank-difference correlation | the most commonly used method of computing a correlation coefficient between the ranks of scores on two variables |
Kendall partial rank correlation | a nonparametric measure of partial correlation |
coefficient of concordance | a coefficient of agreement (concordance) between different sets of rank orderings of the same set of things |
tau coefficient of correlation Kendall's tau Kendall rank correlation | a nonparametric measure of the agreement between two rankings |
phi coefficient phi correlation fourfold point correlation | an index of the relation between any two sets of scores that can both be represented on ordered binary dimensions (e.g., male-female) |
split-half correlation chance-half correlation | a correlation coefficient calculated between scores on two halves of a test, taken as an indication of the reliability of the test |
tetrachoric correlation coefficient tetrachoric correlation | a correlation coefficient computed for two normally distributed variables that are both expressed as a dichotomy |
spurious correlation | a correlation between two variables (e.g., between the number of electric motors in the home and grades at school) that does not result from any direct relation between them (buying electric motors will not raise grades) but from their relation to other variables |
coefficient | a constant number that serves as a measure of some property or characteristic |
absorption coefficient coefficient of absorption absorptance | a measure of the rate of decrease in the intensity of electromagnetic radiation (as light) as it passes through a given substance, the fraction of incident radiant energy absorbed per unit mass or thickness of an absorber, absorptance equals minus transmittance |
drag coefficient coefficient of drag | the ratio of the drag on a body moving through air to the product of the velocity and the surface area of the body |
coefficient of friction | the ratio of the weight of an object being moved along a surface and the force that maintains contact between the object and the surface |
coefficient of mutual induction mutual inductance | a measure of the induction between two circuits, the ratio of the electromotive force in a circuit to the corresponding change of current in a neighboring circuit, usually measured in henries |
coefficient of self induction self-inductance | the ratio of the electromotive force produced in a circuit by self-induction to the rate of change of current producing it, expressed in henries |
coefficient of elasticity modulus of elasticity elastic modulus | (physics) the ratio of the applied stress to the change in shape of an elastic body |
coefficient of expansion expansivity | the fractional change in length or area or volume per unit change in temperature at a given constant pressure |
coefficient of reflection reflection factor reflectance reflectivity | the fraction of radiant energy that is reflected from a surface |
coefficient of viscosity absolute viscosity dynamic viscosity | a measure of the resistance to flow of a fluid under an applied force |
correlation correlativity | a reciprocal relation between two or more things |