Table 1.

Results of Monte Carlo Simulations Carried Out to Estimate the Bias and Standard Error of the Maximum Likelihood Estimators of the Model Parameters in a Mixture Model of Breast Cancer Disease Progression^a

Parameter Type	Maximum Likelihood Estimator								Type II Errorb
	Fraction of Indolent Tumors		Rate of Progression to Clinical Disease		Rate of Onset of Preclinical Cancer		Screening Sensitivity
	$\mathbf{\psi }$	$\mathbf{SE}\mathbf{(}\stackrel{\mathbf{ˆ}}{\mathbf{\psi }}\mathbf{)}$	$\mathbf{\lambda }$	$\mathbf{SE}(\stackrel{\mathbf{ˆ}}{\mathbf{\lambda }})$	$\mathit{w}$	$\mathbf{S}\mathbf{E}(\stackrel{\mathit{ˆ}}{\mathit{w}})$	$\mathbf{\beta }$	$\mathbf{SE}(\stackrel{\mathbf{ˆ}}{\mathbf{\beta }})$
Target	0.2000		0.4000		0.0025		0.8000
Estimate	0.2002	0.0270	0.4056	0.0593	0.0025	0.0001	0.8007	0.0231	0.000

Abbreviation: SE, standard error.

^a Example target and estimated parameters based on 1,000 Monte Carlo simulations.

^b Where the null hypothesis, $H_0:\mathrm{\psi }=0$, was not rejected.