In order to obtain a biased
stratified sample, we simulated a two-phase random selection process from the population (Figure 1(a)) such that P(Y = 1 | S) = 0.5 and P([X.sub.e] = 1 | S) = 0.5.
Is there a difference in school-wide student pass rates on Math assessments between an experimental group of elementary, middle, and secondary RAMP-designated schools (2007) and a
stratified sample of control schools over time (from 2005-2006 to 2008-2009)?
On the basis of GAO's review of a
stratified sample of FDA's 3R incentive files awarded from January 2007 through October 2008, GAO found that FDA maintained documentation which provided sufficient explanation to justify each award.
Due to these issues, sample size in terms of number of clusters and items selected from each cluster should be greater than the sample size required for a simple random sample or
stratified sample.
Prior to adopting new materials the curriculum, Anderson told her, district leaders sent surveys to a random
stratified sample of parents, asking them how they felt about what the district was teaching students at every grade level up to that point.
A probabilistic
stratified sample of public and private schools (71) was selected from the eleven health administrative regions of Puerto Rico, according to the type of school and economic status.
All data were pooled in a
stratified sample to estimate overall total coverage in the PPHC area.
does each random
stratified sample meet the requirement to be a SRS.
District Example: A district may want to consider surveying every school administrator in the district, select a
stratified sample of teachers to survey, survey all district administrators, and conduct site visitations in every school that serves students.
Interestingly, the results of a questionnaire on linguistic attitudes and cultural identities distributed to a
stratified sample of 1,440 individuals point to a new positive attitude towards CF, particularly among younger speakers.
In a national survey of a
stratified sample of 1,278 high school students from 14 schools across the country, only 3.7% of the students in consulted their teachers about career planning, although many more consulted their fathers (23%) and mothers (32%).