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NAEP Weighting Procedures → 2002 Weighting Procedures and Variance Estimation → National Main Assessment Weights → Calculation of Replicate Weights → Computing School-Level Replicate Weights

NAEP Technical Documentation Computing School-Level Replicate Weights

Within each doublet preliminary stratum (each stratum with two units), the first school was assigned as the first variance unit and the second school as the second variance unit. Within each triplet preliminary stratum, the three schools were assigned variance units 1 through 3. With ws as the full sample base weight (the inverse of the school's probability of selection) for school s, Rr as the schools within the r-th replicate stratum, and Us as the variance unit (1 or 2), the replicate weights ws(r), r = 1,...,R, can be represented as:

w subscript s open paren r close paren equals open paren two times w subscript s if s is an element of cap r subscript r and cap u subscript s equals one close paren or equals open paren zero if s is an element of cap r subscript r and cap u subscript s equals two close paren or equals open paren w subscript s if s is an element of cap r subscript r close paren

For triplets (strata with three units), each triplet replicate stratum Rr was assigned a paired replicate stratum r2 . The replicate weights assigned to schools in Rr were as follows:

w subscript s open paren r close paren equals open paren one point five times w subscript s if s is an element of cap r subscript r and cap u subscript s equals one close paren or equals open paren one point five times w subscript s if s is an element of cap r subscript r and cap u subscript s equals two close paren or equals open paren zero if s is an element of cap r subscript r and cap u subscript s equals three close paren or equals open paren w subscript s if s is an element of cap r subscript r close paren w subscript s open paren r subscript two close paren equals open paren one point five times w subscript s if s is an element of cap r subscript r and cap u subscript s equals one close paren or equals open paren zero if s is an element of cap r subscript r and cap u subscript s equals two close paren or equals one point five times w subscript s if s is an element of cap r subscript r and cap u subscript s equals three close paren or equals open paren w subscript s if s is an element of cap r subscript r close paren

Last updated 04 March 2009 (RF)

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