Table 6. Fetal mass models (mass in g vs. gestational age in weeks).

Model	${\widehat{\mathit{\theta }}}_0$	${\widehat{\mathit{\theta }}}_1$	${\widehat{\mathit{\theta }}}_2$	${\widehat{\mathit{\theta }}}_3$	$\mathcal{l}\left(\widehat{\mathit{\theta }}\right)$	AIC
Linear Growth	2.0609	—	—	—	-1.3×106	2.6×106
Quadratic Growth	-14.715	2.4326	—	—	-288832	577668
Cubic Growth	0.11563	0.061459	0.045199	—	-285330	570666
Gompertz	0.0018282	1.1735	0.077577	—	-258093	516193
Logistic	3680.3	0.29875	31.205	—	-259854	519714

For each model considered, the maximum likelihood parameter estimates ($\widehat{\theta }$), log-likelihood ($\mathcal{l}\left(\widehat{\theta }\right)$), and AIC are provided. The row describing the selected model is shown in boldface.