Spencer, Bruce D. <br/><br/>
Sampling probabilities for aggregations, with application to NELS:88 and other educational longitudinal surveys 

 - 21-34 
 - 16, No. 1, 1991 
<br/><br/>Julio 1991 
 = JOURNAL OF EDUCATIONAL STATISTICS 
<br/><br/><label>Encabezamiento--Término de Indización: </label>AVALUO EDUCATIVO ESTUDIO LONGITUDINAL INSPECCIONES NACIONALES MUESTREO PROBABILIDAD