To model the melt-spinning process of biodegradable as-spun linear aliphatic-aromatic copolyester fibers, a fraction factorial experimental design and appropriate statistical analysis for the 32 screening trials involving five control parameters were used. Because of their central role in the production processes and end use textiles, it is important to simulate the mechanical and thermal shrinkage properties of AAC fibers. Concise statistical models of fiber behavior are based on factorial experimental design data. Process's data are collected, analyzed, and mathematical models created to predict the diameter, tenacity, elongation at break, modulus, and thermal shrinkage of the spun fiber in terms of random variables and their associated probability distributions. The theoretical regression models obtained form the main source code in the enhanced forecasting program, which presents the melt-spinning process of aromatic-aliphatic copolyester fibers. Factorial statistical approaches, based on over indicated region levels of melt-spinning process parameters, are given in terms of assumptions and theory to produce biodegradable, environmentally friendly fibers for different applications. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 1434-1449, 2011