Two-stage Sample Design with Small Clusters
نویسنده
چکیده
In two-stage surveys, the sample size of clusters and units within clusters can be chosen to minimise the variance of an estimator, for fixed cost. This paper considers sample designs where the number of units to be selected from each cluster is a function of the cluster size. If there are only a small number of units in each cluster, as in household surveys, then the optimisation should be over integers. An integer programming method is developed which gives significantly lower variances than traditional methods. A non-integer within-cluster sample size can be implemented by using a mixture of several integers; this can further reduce the variance.
منابع مشابه
Accounting for Multi - stage Sample Designs in Complex Sample Variance
Nationally representative samples of large populations often have complex design features for a variety of reasons (e.g., cost efficiency). For purposes of estimating sampling variances based on complex multi-stage sample designs involving stratification and cluster sampling, the sampling error codes provided by survey organizations in public use survey data files often assume “ultimate cluster...
متن کاملThe effect of nonrandom selection of clusters in a two stage cluster design
THE EFFECT OF NONRANDOM SELECTION OF CLUSTERS IN A TWO STAGECLUSTER DESIGN byJASON PARROTTDecember 2012Advisor: Dr. Shlomo SawilowskyMajor: Evaluation and ResearchDegree: Doctor of Philosophy Although not as efficient as simple random sampling, cluster sampling has beenregarded as a valid sampling technique when the researcher is attempting to save cost. However,...
متن کاملDesign of Economic Optimal Double Sampling Design with Zero Acceptance Numbers
In zero acceptance number sampling plans, the sample items of an incoming lot are inspected one by one. The proposed method in this research follows these rules: if the number of nonconforming items in the first sample is equal to zero, the lot is accepted but if the number of nonconforming items is equal to one, then second sample is taken and the policy of zero acceptance number would be ap...
متن کاملOn determination of sample size in hierarchical binomial models.
We consider a two- and a three-stage hierarchical design containing the effects of k clusters with n units per cluster. In the two-stage model, the conditional distribution of the discrete response Y(i) is assumed to be independent binomial with mean n(straight theta)i (I=1,....k). The success probabilities, straight theta(i)'s, are assumed exchangeable across the k clusters, each arising from ...
متن کاملSampling in health geography: reconciling geographical objectives and probabilistic methods. An example of a health survey in Vientiane (Lao PDR)
BACKGROUND Geographical objectives and probabilistic methods are difficult to reconcile in a unique health survey. Probabilistic methods focus on individuals to provide estimates of a variable's prevalence with a certain precision, while geographical approaches emphasise the selection of specific areas to study interactions between spatial characteristics and health outcomes. A sample selected ...
متن کامل