Analisis pengaruh ownerships, debt to total assets, collateralizable assets dan free cash flow terhadap dividend payout ratio : studi empiris pada perusahaan sektor non keuangan yang tercatat di Bursa Efek Indonesia (BEI) pada periode tahun 2009-2011 = Analysis of the effect of ownerships, debt to total assets, collateralizable assets and free cash flow on dividend payout ratio : a study of non financial firms listed in Indonesia Stock Exchange for the period 2009-2011