For each of the sixteen dependent portfolios a regression analysis has been conducted in
compliance with the model: Rit - Rft = a + bi[Rmt-Rft] + siSMBt)+ hiHMLt + εit
In table 2 the intercept and its related p-values, the coefficients for the explanatory variables
as well as the value of the adjusted r-squared are presented for the period of 2005 - 2009
The fact that α is positively significant at the 5 % level for two of the portfolios means, that
the model underestimates the returns for those portfolios, 2_L and B_L. If the intercept had
been negatively significant, the model would have overestimated the return of the portfolio in
question.
To measure the level of explanation we use the adjusted R². The reason for doing this is
because we are comparing the level of explanation for two models with different number of
explanatory variables. The value of the unadjusted R² will always increase as the number of
variables increase, while the adjusted R² takes the loss of degrees of freedom related to adding
extra variables into consideration80. The value of the adjusted R² in the regressions above lies
between 41 % and 88 %.