flory fox, kurata-stockmayer, berry, inagaki-suzuki-kurata, stockmayer-fixman and ahmad-baloch methods based on the excluded volume theory have been applied to poly(vinyl chloride)-cyclohexanone system to obtain kq and the radius of gyration. a discussion on the reliability of these methods is given. the stockmayer-fixman and ahmad-baloch methods are found to be equally applicable.