This is the objective function used to solve for p lambda parameters. The objective function involves p simultaneous equations corresponding to p covariates used in the model. Let tilda cap T sub x denote the control total for covariate x. The adjusted weight for person k is obtained by taking the product of the original design weight, d sub k, and the adjustment factor a sub k of lambda. Then the objective function equation for covariate x is defined as the sample weighted (using adjusted weight) sum of covariate x equal to the control total for covariate x.