Table 3. Estimated parameter values and MSPEs for the OLS, the 2SLS, the Ridge and 2SLS-R methods.

Estimation	${\hat{\beta }}_{ols}$	${\hat{\beta }}_{2sls}$	${\hat{\beta }}_{ridge}$	${\hat{\beta }}_{2sls-r}$
Intercept	0.0055	0.0064	0.0055	0.0061
$\widehat{{\beta }_1}$	−0.1747	−5.868	−0.1707	−3.5670
$\widehat{{\beta }_2}$	0.2384	1.5041	0.2280	0.8182
$\widehat{{\beta }_3}$	0.0565	4.1146	0.0502	2.6057
Estimated MSPE	0.9914	0.9882	0.9901	0.9832