stratified sample

(redirected from stratified samples)
Also found in: Dictionary, Thesaurus, Encyclopedia.
Related to stratified samples: Stratified random sampling

strat·i·fied sam·ple

a subset of a total population, defined by some objective criterion such as age or occupation, is sampled.
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
We refer to this technique as IP oversampling: Since in the stratification process some observations were oversampled, this method is a way of reoversampling underrepresented observations in the stratified sample. Since IP oversampling is applicable to arbitrary classifiers, we take it into account for further comparisons.
Stratified samples ensure that the sample proportion for the stratifying characteristic is identical to the population proportion, reducing sampling error and improving the accuracy of inferences.
Number of depth- Haul Date Time Day or night stratified samples HH-05A 3 Aug 2000 1600 Day 8 HH-05B 5 Aug 2000 2356 Night 8 HH-05C 6 Aug 2000 0330 Night 8 HH-05D 6 Aug 2000 0630 Day 8 HH-05E 6 Aug 2000 1623 Day 9 HH-05F 7 Aug 2000 0343 Night 9 HH-05G 7 Aug 2000 0633 Day 7 HH-05B 11 Aug 2002 0350 Night 9 HH-05C 11 Aug 2002 0722 Day 8 Table 2 Day, night, and total mean densities (number/1000 [m.sup.3]) of fish eggs collected at all different depth strata from a single offshore station off the central Oregon coast in 2000 and 2002 (1 standard error in parentheses).
However, these studies were carried out on relatively small stratified samples taken at convenience (24,25).