COMMENT: Run the linear model (OLS; Ordinary Least Squares).
REGRESSION
  /MISSING LISTWISE
  /STATISTICS COEFF OUTS R ANOVA
  /CRITERIA=PIN(.05) POUT(.10)
  /NOORIGIN
  /DEPENDENT mathach
  /METHOD=ENTER ses  .

COMMENT: Run the Null Multilevel Model - Null Model.
MIXED
  mathach
  /CRITERIA = CIN(95) MXITER(100) MXSTEP(5) SCORING(1) SINGULAR(0.000000000001) HCONVERGE(0, ABSOLUTE) LCONVERGE(0, ABSOLUTE) PCONVERGE(0.000001, ABSOLUTE)
  /FIXED = | SSTYPE(3)
  /METHOD = REML
  /PRINT = SOLUTION TESTCOV
 /RANDOM INTERCEPT  | SUBJECT(school) COVTYPE(VC) .

COMMENT: Run the Model with Fixed Effect for Slopes - Model One.
MIXED
  mathach  WITH cses
  /CRITERIA = CIN(95) MXITER(100) MXSTEP(5) SCORING(1) SINGULAR(0.000000000001) HCONVERGE(0, ABSOLUTE) LCONVERGE(0, ABSOLUTE) PCONVERGE(0.000001, ABSOLUTE)
  /FIXED = cses  | SSTYPE(3)
  /METHOD = REML
  /PRINT = SOLUTION TESTCOV
 /RANDOM INTERCEPT  | SUBJECT(school) COVTYPE(VC) .

COMMENT: Add a Random Component to the Slopes - Model Two.
MIXED
  mathach  WITH cses
  /CRITERIA = CIN(95) MXITER(100) MXSTEP(5) SCORING(1) SINGULAR(0.000000000001) HCONVERGE(0, ABSOLUTE) LCONVERGE(0, ABSOLUTE) PCONVERGE(0.000001, ABSOLUTE)
  /FIXED = cses  | SSTYPE(3)
  /METHOD = REML
  /PRINT = SOLUTION TESTCOV
 /RANDOM INTERCEPT cses  | SUBJECT(school) COVTYPE(VC) .

COMMENT: Add meanses as a predictor of both the intercept and the slope of ses - Model Three.
MIXED
  mathach  WITH cses meanses
  /CRITERIA = CIN(95) MXITER(100) MXSTEP(5) SCORING(1) SINGULAR(0.000000000001) HCONVERGE(0, ABSOLUTE) LCONVERGE(0, ABSOLUTE) PCONVERGE(0.000001, ABSOLUTE)
  /FIXED = cses meanses cses*meanses  | SSTYPE(3)
  /METHOD = REML
  /PRINT = SOLUTION TESTCOV
 /RANDOM INTERCEPT cses  | SUBJECT(school) COVTYPE(VC) .

COMMENT: Add sector as a predictor of both the intercept and the slope of ses - Model Four.
MIXED
  mathach  WITH cses meanses sector
  /CRITERIA = CIN(95) MXITER(100) MXSTEP(5) SCORING(1) SINGULAR(0.000000000001) HCONVERGE(0, ABSOLUTE) LCONVERGE(0, ABSOLUTE) PCONVERGE(0.000001, ABSOLUTE)
  /FIXED = cses meanses cses*meanses sector cses*sector  | SSTYPE(3)
  /METHOD = REML
  /PRINT = SOLUTION TESTCOV
 /RANDOM INTERCEPT cses  | SUBJECT(school) COVTYPE(VC) .