NAEP Technical DocumentationComputing School-Level Replicate Base Weights for the 2014 Assessment

For the NAEP 2014 assessment, school-level replicate base weights for school s in primary stratum j (SCH_BWTjs(r), r = 1,..., 62) were calculated as follows:

                       

SCH underscore BWT subscript js open paren r close paren equals open paren two times SCH underscore BWT subscript js for js is a

 

where

  • SCH_BWTjs is the school base weight for school s in primary stratum j,

  • Rjr is the set of schools within the r-th replicate stratum for primary stratum j, and

  • Ujs is the variance unit (1 or 2) for school s in primary stratum j.

For schools in replicate strata comprising three variance units, two sets of school-level replicate base weights were computed (see replicate variance estimation for details): one for the first replicate r1  and another for the second replicate r2. The two sets of school-level replicate base weights SCH_BWTjs(r1), r1 = 1,..., 62 and SCH_BWTjs(r2), r2 = 1,..., 62 were calculated as described below.  

                       

SCH underscore BWT subscript js open paren r subscript one close paren equals open paren one point five times SCH underscore BWT



SCH underscore BWT subscript js open paren r subscript two close paren equals open paren one point five times SCH underscore BWT

 

where

  • SCH_BWTjs is the school base weight for school s in primary stratum j,

  • Rjr1 is the set of schools within the r1-th replicate stratum for primary stratum j,

  • Rjr2 is the set of schools within the r2-th replicate stratum for primary stratum j, and

  • Ujs is the variance unit (1, 2, or 3) for school s in primary stratum j. 

Last updated 14 April 2021 (SK)