Table 3 Parameter estimates (approximated standard error in parentheses) for the models analyzed
From: Stem taper function for sweet chestnut (Castanea sativa Mill.) coppice stands in northwest Spain
Parameter | Fang et al. (2000) | Bi (2000) | Kozak (2004) | Demaerschalk (1972) | Thomas and Parresol (1991) |
|---|---|---|---|---|---|
a 0 | 5.542 × 10−5 (3.7 × 10−6) | 0.8600 (0.029) | |||
a 1 | 1.914 (0.015) | 0.9781 (0.0084) | |||
a 2 | 0.936 (0.027) | 0.08444 (0.015) | |||
b 0 | 1.520 (0.061) | ||||
b 1 | 9.869 × 10−6 (1.61 × 10−7) | Convergence was not achieved | 0.7844 (0.029) | 0.9567 (0.0098) | −1.00228 (0.0065) |
b 2 | 3.362 × 10−5 (2.99 × 10−7) | −0.3341 (0.040) | 0.8898 (0.0070) | 0.1107 (0.0036) | |
b 3 | 2.667 × 10−5 (3.79 × 10−7) | 0.4866 (0.016) | −0.9378 (0.019) | 3.851 × 10−7 (2.93 × 10−8) | |
b 5 | −0.01954 (0.0021) | ||||
b 6 | 0.2318 (0.026) | ||||
p 1 | 0.07191 (0.0014) | 0.7258 (0.025) | 0.8367 (0.024) | ||
p 2 | 0.5590 (0.0101) | 0.3936 (0.020) | 0.3639 (0.019) |