| chi-square distribution | A distribution in which a variable is distributed like the sum of the the squares of any given independent random variable, each of which has a normal distribution with mean of zero and variance of one. The chi-square test is a statistical test based on comparison of a test statistic to a chi-square distribution. The oldest of these tests are used to detect whether two or more population distributions differ from one another. (12 Dec 1998) |
|---|---|
| multinomial distribution | Probability distribution associated with the classification of each of a sample of individuals into one of several mutually exclusive and exhaustive categories. (05 Mar 2000) |
| contagious distribution | <epidemiology> Same as an aggregated distribution. (05 Dec 1998) |
| poisson distribution | <epidemiology> The distribution which arises when parasites are distributed at random amongst hosts. (05 Dec 1998) |
| countercurrent distribution | A method of separation of two or more substances by repeated distribution between two immiscible liquid phases that move past each other in opposite directions. It is a form of liquid-liquid chromatography. (12 Dec 1998) |
| hospital distribution systems | Systems for delivering hospital supplies, food, laundry, etc., to patient care areas. (12 Dec 1998) |
| sex distribution | The number of males and females in a given population. The distribution may refer to how many men or women or what proportion of either in the group. The population is usually patients with a specific disease but the concept is not restricted to humans and is not restricted to medicine. (12 Dec 1998) |
| skew distribution | An asymmetrical frequency distribution; in biology and medicine it is usually a lognormal distribution. (05 Mar 2000) |
| negative binomial distribution | <epidemiology> A distribution which is parameterised by a mean m and an aggregation parameter k which is large when aggregation is small; in fact as k becomes large, the negative binomial distribution approximates the Poisson distribution. (05 Dec 1998) |
| nitrogen distribution | Determination of the distribution of nitrogen in the urine among the various constituents. Synonym: nitrogen distribution. (05 Mar 2000) |
| normal distribution | Continuous frequency distribution of infinite range. Its properties are as follows: 1) continuous, symmetrical distribution with both tails extending to infinity; 2) arithmetic mean, mode, and median identical; and 3) shape completely determined by the mean and standard deviation. (12 Dec 1998) |
| dermatomal distribution | The area of skin innervated by a single posterior spinal nerve (sensory nerve). (27 Sep 1997) |
| distribution | 1. The specific location or arrangement of continuing or successive objects or events in space or time. 2. The extent of a ramifying structure such as an artery or nerve and its branches. 3. The geographical range of an organism or disease. 4. Probability. Origin: L. Distributio (11 Jan 1998) |
| distribution coefficient | The ratio of concentrations of a substance in two immiscible phases at equilibrium; the basis of many chromatographic separation procedures. Synonym: partition coefficient. (05 Mar 2000) |
| distribution curve | A systematic grouping of data into classes or categories according to the frequency of occurrence of each successive value or ranges of such values, resulting in a graph of a frequency distribution. Synonym: frequency curve. (05 Mar 2000) |