With the assumption that segregating alleles are at equilibrium and conditioned on observing a segregating allele using binomial sampling, the probability of sampling a deleterious allele more than once among 44 chromosomes is around 2.1% (the probability of sampling nonsingletons divided by the probability of sampling a segregating allele at least once).
Yet unless the training sample is collected by probability sampling, the estimates are, at best, of uncertain quality, and may be substantially biased.
Future studies involving a larger or more random selection of practices or studies which recruit subjects from the general population by probability sampling may help to strengthen the generalizability of the study findings.
By incorporating probability sampling in both the spatial and temporal domains, the present study establishes the foundation for rigorous design-based validation of global burned area products and, more generally, of terrestrial thematic products that have high temporal variability.
The primary sampling units were selected by a probability sampling with inclusion probabilities proportional to the population of each unit.
Because design-based inference requires a probability sampling design, directing volunteers to locations specified by a probability sampling design is the most straightforward option for use of VGI in design-based inference.
The cohort was selected by probability sampling from 4 US communities: Forsyth County, North Carolina Jackson, Mississippii; the northwest suburbs of Minneapolis, Minnesota; and Washington County, Maryland.
Sampling locations were selected by probability sampling, so that in estimating the target quantities no model assumptions on the spatial variation were required, and valid estimates could be obtained by design-based inference.
During the period from 1991 through 1997, participants were recruited by probability sampling from six townships in the county.
