MULTIPOPULATION SURVEY DESIGNS - 5 TYPES WITH 7 SHARED ASPECTS

Five types of multipopulation surveys are defined and described: perio dic surveys; multidomain designs; multinational survey designs, cumula ted and combined samples; and controlled observations or quasi-experim ental designs. I emphasize the deliberate designs of these surveys, no t the mere post hoc or ad hoc utilization of survey results. Most impo rtantly, I emphasize a sharp distinction between seven listed aspects. Similarity and standardization of the survey aspects (definitions, me thods, measurements) are essential to avoid biases in comparisons, tho ugh admittedly difficult. In contrast, flexibility in sampling designs and sizes, to reduce variances, is permissible, also desirable to red uce variances and costs. This divergence in strategies still needs to be understood and applied.