back to SurveySampling :StratifiedSampling -- MultistageSampling? -- SimpleRandomSampling? A geographically dispersed population can be very expensive to survey with personal interviews due to extravagant travel costs. Greater economy than random sampling can be achieved by including several respondents within a local area. It is usually necessary to increase the total sample size to achieve equivalent precision in the estimators, but the savings in cost may make that feasible. DickBeldin |
see Cluster Sampling |