本文運用擇偶網站資料，比較台灣與日本男女的擇偶年齡門檻差異，以驗證並修改South (1991) 有關婚姻市場壓力對擇偶年齡偏好影響的理論。由於日本的適婚年齡人口性比例比台灣更高，日本男性較台灣男性處於更「劣勢」的婚姻市場中。本文實證得出，日本男性的年齡上門檻較台灣男性高，而年齡下門檻與台灣男性差不多，顯示處於更「劣勢」中的日本男性更放寬年齡上門檻以增加擇偶機會。反之，由於日本女性處於更「優勢」的婚姻市場中，日本女性的年齡上門檻較台灣女性更低，顯示更能拒絕高年齡男性。而日本女性的年齡下門檻也比台灣女性更低，顯示更有自信獲得較低年齡男性的接受。對於年齡下門檻在年齡偏好中所代表的涵義，本文也在討論結果中，付予了新的定義。

This study used data from matching websites to examine the sex ratio effect on age preference between highly-educated Taiwanese and Japanese. The results indicated that Japanese men have higher ceiling-age threshold than Taiwanese men. In contrast, Japanese women have both lower ceiling-age and floor-age thresholds than Taiwanese women. This confirms South’s (1991) argument, that the people who face bleak marriage market will adjust their mating preference to broaden their marriage opportunity. Because the sex ratio of marriageable age in Japan is higher than in Taiwan, Japanese men confront larger marriage squeeze than Taiwanese men do. Since Japanese face a less favorable marriage market, they enhance their marriage opportunity by setting a higher ceiling-age criteria of age preference. In contract, Japanese women enjoy a favorable marriage market than Taiwanese women do. Therefore Japanese women have more confidence by setting a lower ceiling-age criteria to reject older men and a lower floor-age criteria to attract younger men.