| haphazard | Lacking any coherent system, organization, or objective; not to be confused with random or chaotic. (05 Mar 2000) |
|---|---|
| haphazard sampling | The assembly of data in an unprescribed and undefined fashion that allows no sound scientific inferences other than establishing the existence of types. (Finding even one unicorn in such a set would establish that unicorns can exist, but no inference about their prevalence could be made from it.) Cf.: random sample. (05 Mar 2000) |
| Rahn-Otis sample | An approximation of alveolar gas continuously provided by a simple device that admits just the latter part of each expiration. (05 Mar 2000) |
| random sample | A group selected randomly, solely by chance. (12 Dec 1998) |
| Haldane-Priestley sample | <physiology> An approximation of alveolar gas obtained from the end of a sudden maximal expiration into a Haldane tube. (05 Mar 2000) |
| probability sample | Each individual in the sample has a known, generally equal, chance of being selected. (05 Mar 2000) |
| sample | 1. A specimen of a whole entity small enough to involve no threat or damage to the whole; an aliquot. 2. A selected subset of a population; a sample may be random or nonrandom (haphazard); representative or nonrepresentative. Origin: M.E. Ensample, fr. L. Exemplum, example (05 Mar 2000) |
| sample, random | A group selected randomly, solely by chance. (12 Dec 1998) |
| sample size | The number of units (persons, animals, patients, specified circumstances, etc.) in a population to be studied. The sample size should be big enough to have a high likelihood of detecting a true difference between two groups. (12 Dec 1998) |
| stratified sample | A subset of a total population, defined by some objective criterion such as age or occupation, is sampled. (05 Mar 2000) |
| end-tidal sample | A sample of the last gas expired in a normal expiration, ideally consisting only of alveolar gas. (05 Mar 2000) |