NAEP Assessment Sample Design → NAEP 2009 Sample Design → Sample Design for the 2009 National Assessment → Hands-On Tasks (HOT) and Interactive Computer Tests (ICT) for the 2009 Science Assessment → Selection of Primary Sampling Units (PSUs) for the 2009 Science HOT and ICT Assessments → Primary Sampling Unit Frame: Stratification → Final Primary Sampling Unit (PSU) Strata

NAEP Technical DocumentationFinal Primary Sampling Unit (PSU) Strata

The strata were defined using the selected stratifiers from the stepwise regression analysis (see Stepwise Regression Analysis Results for PSU Stratification). The cutoffs were selected so that roughly equal measures of size were represented by each stratum.

Stratification for Northeast metropolitan noncertainty primary sampling units (PSUs), by stratum: 2009

Stratum	Primary stratifier	Secondary stratifier	PSUs	Measure of size
† Not applicable. NOTE: Black includes African American. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2009.
Total	†	†	46	4,610,832
1	Percent child poverty <=10.1%	Percent Black <=15.9%	8	577,328
2	Percent child poverty <=10.1%	15.9%< Percent Black <=27.7%	2	540,692
3	10.1%< Percent child poverty <=12.5%	Percent Black <=14.9%	7	584,614
4	10.1%< Percent child poverty <=12.5%	14.9%< Percent Black <=38.2%	4	623,303
5	12.5%< Percent child poverty <=13.4%	†	5	547,256
6	13.4%< Percent child poverty <=15.1%	†	7	591,136
7	15.1%< Percent child poverty <=17%	†	5	537,824
8	17%< Percent child poverty <=20.7%	†	8	608,679
Mean	†	†	†	576,354

Stratification for Northeast non-metropolitan noncertainty primary sampling units (PSUs), by stratum: 2009

Stratum	Primary stratifier	PSUs	Measure of size
† Not applicable. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2009.
Total	†	50	1,133,461
1	Percent child poverty <=15.7%	23	577,961
2	15.7%< Percent child poverty <=22.8%	27	555,500
Mean	†	†	566,731

Stratification for Midwest metropolitan noncertainty PSUs, by stratum: 2009

Stratum	Primary stratifier	Secondary stratifier	Tertiary stratifier	PSUs	Measure of size
Total	†	†	†	100	7,397,196
1	Child poverty <=12.5%	†	Pct Asian <=1.1%	17	622,942
2	Child poverty <=12.5%	†	1.1%< Pct Asian <=1.4%	4	644,774
3	Child poverty <=12.5%	†	1.4%< Pct Asian <=2.4%	8	590,163
4	Child poverty <=12.5%	†	2.4%< Pct Asian <=2.6%	3	684,275
5	Child poverty <=12.5%	†	2.6%< Pct Asian <=3.4%	7	591,480
6	Child poverty <=12.5%	†	3.4%< Pct Asian <=10.3%	13	604,864
7	12.5%< Child poverty <=12.9%	†	†	6	613,852
8	12.9%< Child poverty <=14.5%	†	Pct Asian <=1.3%	7	622,305
9	12.9%< Child poverty <=14.5%	†	1.3%< Pct Asian <=2.7%	7	609,868
10	14.5%< Child poverty <=27.6%	Med Income <=$38,291	†	17	606,714
11	14.5%< Child poverty <=27.6%	$38,291< Med Income <=$46,460	Pct Asian <=0.9%	7	580,754
12	14.5%< Child poverty <=27.6%	$38,291< Med Income <=$46,460	0.9%< Pct Asian <=3.1%	4	625,205
Mean	†	†	†	†	616,433

Stratification for West non-metropolitan noncertainty primary sampling units (PSUs), by stratum: 2009

Stratum	Primary stratifier	Secondary stratifier	Tertiary stratifier	PSUs	Measure of Size
† Not applicable. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2009.
Total	†	†	†	102	1,704,176
1	Percent college graduates <=21%	Median child poverty <=17.3%	†	26	426,857
2	Percent college graduates <=21%	17.3%< Median child poverty <=43%	Percent HS graduates <=77.3%	23	423,420
3	Percent college graduates <=21%	17.3%< Median child poverty <=43%	77.3%< Percent HS graduates <=86.4%	28	422,921
4	21%< Percent college graduates <=42.6%	†	†	25	430,978
Mean	†	†	†	†	426,044

Printer-friendly Version