行動電話服務市場自1997年開放迄今，市場競爭日趨激烈。業者仍不時以優惠的費率方案，企圖擴張市場佔有率，其效果如何？頗值得探討。本研究基於間斷選擇理論，以機率性價格門檻模式探討行動電話使用者在選擇門號品牌時所產生之利得或損失知覺，進而分析消費者之價格敏感度，以供業者擬定行銷策略之參考。研究結果顯示：（1）明顯影響使用者之利得價格門檻的因素有：「業者之價格定位」、「競爭者之相對通話費用」以及「通話量」等變數；（2）消費者對價格定位較低之業者，其心中之價格門檻較高，對利得知覺較不敏感；（3）當實際費用低於消費者心中之參考價格時，某業者之費率相較其它業者費率愈便宜，愈能使消費者產生利得知覺；（4）對價格敏感度較低之消費者而言，價格變動對利得及損失門檻有不對稱的效果。換言之，此類消費者較易產生損失知覺；（5）使用利得（損失）機率為區隔變數並以集群分析法進行市場區隔，可區隔出「高價格敏感度」與「低價格敏感度」之消費族群，此兩族群在通話量上有顯著差異，高價格敏感度者之通話量較大。業者可根據消費族群之特性進行不同的促銷策略。

In this study, based on discrete choice theory, we construct a probabilistic threshold price model to analyze cellular phone user's brand choice behavior and price sensitivity. Major findings of this study are as follows. (1) Factors that significantly affect user's price thresholds are price policy of the companies, relative usage fee, and communication quantities. (2) Consumers who think company has low price policy are less senstitive to gains and more sensitive to losses. (3) When actual price is lower than reference price, the higher relative usage fee of competing companies makes consumers more sensitive to gains and less sentitive to lesses. (4) As for consumers with low price sensitivity, price changes have asymmetric effects on gain and loss thresholds. In other words, such consumers are more sensitive to losses. (5) Using gain (loss) probability as segment variable, consumers can be separated into high price sensitivity and low price sensitivity groups. There exists significant difference in quality consumed between these two groups. High price sensitivity group has larger quantity of communication.