本研究以不可補償決策理論中之EBA模式建立民國68年至78年間三級產業人口之遷 移區位選擇模式，藉以探討影響三級產業人口遷移之區位屬性其重要優先順序，並分析各屬 性對遷移影響之門檻。方案選擇架構分為上層之區域選擇及下層之次區域選擇，並以階層之 EBA 模式處理之，以避免區位選擇替選方案太多之難題。為比較不同遷出區域及不同遷移時 期的遷移者之遷移特性，特將樣本依遷出區域及遷移時期作區隔，分別建立其遷移模式。實 證分析結果顯示，三級產業人口遷移時之區域選擇，北、中部之遷移者以各區域三級產業人 口之聚集程度為最重要之影響因素，而南部區域之遷移者則受所得差異因素之影響最大。而 「三級產業人口比例」該屬性之影響門檻為最優方案 (北部區域 ) 之 61%， 「平均所得」 之影響門檻則為最優方案 (北部區域 ) 之 75%。 在各區域內之次區域選擇，「平均所得」 該因素其影響門檻較為穩定， 各區域皆為最優方案 (區域中心都市 ) 平均所得水準之 70% 至 80%。「縣市平均每人政府公共支出」該因素之影響門檻在各區域有所不同，北部為台北 市之 50%，中部為台中市之 70%，南部則為高雄市之 43%。上述結果可作為相關政策研擬時 之參考。

　　　　　his study investigates the behavior pattern of locational choice for the migrants employed in the service industry. Elimination-By-Aspects models were estimated using migration data from 1975 to 1989 to study the relative importance and the influential threshold of the locational attributes affecting these migrants. The choice structure is defined as two levels. The upper level is the choice of region, and the lower one is the choice of subarea within each region. For the purpose of comparing the characteristics among the migrants from different regions and at different temporal periods, the sample was segmented into three out-migrant regions and two out-migrant time periods. The empirical study results indicated that 1). In the choice of region, the most important factor influencing the migrants from the northern and central regions is the "ratio of the service industrial employment". The influential threshold is about 61% of the level in the best alternative (the northern region). But income is the most important factor for the southern region's migrants. The influential threshold of the factor "average income" is about 75% of the level in the northern region. 2). In the choice of subarea in a region, the influential threshold of the factor "average income" is stable among regions. It is about 70% to 80% of the level in the central city of every region. The influential threshold of the factor "local government annual payment" is different by regions. It is about 50% of the level in the central city of the northern region, 70% in the central region, and 43% in the southern region. The above conclusions should be helpful in the making of related policy decisions.