THE PROTONATION CONSTANTS OF GLYCINE IN NACL AT 25-DEGREES-C BASED ONTHE PITZER AND SCATCHARD MODELS DATA-ANALYSIS BY RIDGE-REGRESSION

We have potentiometrically determined the protonation constants of gly cine in NaCl solutions of variable ionic strength. The data thus obtai ned have been analysed by using the interaction models of Scatchard an d Pitzer. The presence of multicollinearity among the explanatory vari ables of the model has been evidenced through the coefficients of the correlation matrix and the variance inflation factor (VIF). We have ap plied the ridge regression (RR) to address the problem arising from mu lticollinearity and the results are critically compared with those obt ained by ordinary least squares regression (OLS).