Statistics for Business and Economics, 6/e
... each member of the population is chosen strictly by chance, each member of the population is equally likely to be chosen, and every possible sample of n objects is equally likely to be chosen ...
... each member of the population is chosen strictly by chance, each member of the population is equally likely to be chosen, and every possible sample of n objects is equally likely to be chosen ...
sample
... The population is first divided into groups of elements called strata. Each element in the population belongs to one and only one stratum. Best results are obtained when the elements within each stratum are as much alike as possible (i.e. homogeneous group). A simple random sample is taken fro ...
... The population is first divided into groups of elements called strata. Each element in the population belongs to one and only one stratum. Best results are obtained when the elements within each stratum are as much alike as possible (i.e. homogeneous group). A simple random sample is taken fro ...
Sample Statistics Suppose we have a (finite) population with a
... We consider just two possible methods. In both the probability function for the samples selected is uniform; when the population is finite this means all possible samples are equally likely. In independent random sampling (irs), the sampling is done with replacement, while in simple random sampling ...
... We consider just two possible methods. In both the probability function for the samples selected is uniform; when the population is finite this means all possible samples are equally likely. In independent random sampling (irs), the sampling is done with replacement, while in simple random sampling ...
Crop area estimates with area frames in the presence of
... suggested and the permanent random numbers are used, the two proposed selection procedures for quality control can be assimilated to stratified random sub-sampling Thus, usual direct expansion formulas for area estimates are unbiased, although sample units used for estimating the stratum variability ...
... suggested and the permanent random numbers are used, the two proposed selection procedures for quality control can be assimilated to stratified random sub-sampling Thus, usual direct expansion formulas for area estimates are unbiased, although sample units used for estimating the stratum variability ...
Sampling (statistics)
In statistics, quality assurance, and survey methodology, sampling is concerned with the selection of a subset of individuals from within a statistical population to estimate characteristics of the whole population. Each observation measures one or more properties (such as weight, location, color) of observable bodies distinguished as independent objects or individuals. In survey sampling, weights can be applied to the data to adjust for the sample design, particularly stratified sampling. Results from probability theory and statistical theory are employed to guide practice. In business and medical research, sampling is widely used for gathering information about a population .The sampling process comprises several stages: Defining the population of concern Specifying a sampling frame, a set of items or events possible to measure Specifying a sampling method for selecting items or events from the frame Determining the sample size Implementing the sampling plan Sampling and data collecting Data which can be selected↑ ↑