3.4 Regression of product yield and properties of bio-oil Table V shows that pyrolysis temperature, product yields and bio-oil properties had 2 patterns of regression relationship- linear and quadratic. A total of 21 equations were generated from the statistical analysis. The HHV (wet basis) was correlated with the kinematic viscosity with highest R2 (adj.) of 97%, whereas the regression equation for total bio-oil yield and heavy bio-oil water content shows the lowest R2 (adj.) of 80.4%. The regression models in Table V shows that the total bio-oil