1. coefficient of correlation a statistic representing how closely two variables co-vary
2. tau coefficient of correlation a nonparametric measure of the agreement between two rankings
3. 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
4. coefficient of reflection the fraction of radiant energy that is reflected from a surface
5. coefficient of absorption 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
6. coefficient of expansion the fractional change in length or area or volume per unit change in temperature at a given constant pressure
7. positive 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 0 and +1
8. curvilinear correlation any correlation in which the rates of change of the variables is not constant
9. coefficient of mutual induction a measure of the induction between two circuits
10. 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
11. coefficient of concordance a coefficient of agreement (concordance) between different sets of rank orderings of the same set of things
12. 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
13. negative correlation a correlation in which large values of one variable are associated with small values of the other; the correlation coefficient is between 0 and -1
14. coefficient of self induction 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
15. constant of gravitation (physics) the universal constant relating force to mass and distance in Newton's law of gravitation
16. coefficient of elasticity (physics) the ratio of the applied stress to the change in shape of an elastic body
17. point of accumulation the mathematical value toward which a function goes as the independent variable approaches infinity
18. coefficient of viscosity a measure of the resistance to flow of a fluid under an applied force
19. semantic relation a relation between meanings
20. nonlinear correlation any correlation in which the rates of change of the variables is not constant