Weighting

Unit Level Weights

Nh/nh

Class Level Weights

Nh/N

h being stratums

N is total population

nh being the sampled stratas

Nh being the population stratas

Weighting can be used to adjust for nonresponse if nonrespondents have similar opinions to respondents within weighting classes. Can do this by choosing weighting classes which are strongly related to opinions. Past voting behaviour could also be used.