Difficult# Assessing Residual Plots for Linearity

APSTAT-UKKLIP

Two variables, $x$ and $y$, were taken on $10$ subjects and two separate regression models were fit to the data.

Regression I yielded the following equation and residual plot:

**predicted log y = ax + b**

...where $a$ and $b$ are constants.

Regression II yielded the following equation and residual plot:

**predicted log y = d + log cx**

...where $c$ and $d$ are constants.

Which of the following conclusions is correct?