時間間隔決策的群聚效應：以紐西蘭股市為例

Clustering in Time Span Decisions: Examining the New Zealand Stock Exchange

紐西蘭證券交易所具有二項特徵：第一、紐西蘭市場規模是已開發國家中最小者，第二、發放的股利以紐幣或其他國家貨幣計價。研究發現，發放紐幣公司除息日至發放日間隔天數主要是9天與16天（眾數）。至於發放他國貨幣樣本，主要分佈於23天、30天（眾數）與37天。綜合而言，除息日與發放日間隔天數分佈集中於9天、16天、23天、30天與37天之現象，說明七天的週循環效應對人類時間間隔決策造成重要影響；本研究說明，習慣以七天為一單位之決策行為模式，不利於投資人權益。本研究也建議廢除中華民國公司法第165條「除息基準日前五日停止過戶」之規定，以配合電子化制度，而大幅縮短臺灣市場的除息日與發放日間隔天數，嘉惠投資人。

The NZX is characterized by two features. First, it is the smallest market among the developed countries. Second, the dividends paid by firms are denominated in either NZD or other currencies. Among the events of dividends denominated in NZD, the two mostly common chosen durations between the ex-dividend and payment dates are 9 and 16 days (the mode). As to another independent sample of non-NZD dividends, the three most commonly chosen durations are 23, 30 (the mode), and 37 days. Consequently, these time spans are clustered around from 7 to 37 days, with gaps of 7 days. We confirm the notion that the number 7 plays a salient role in corporate decisions relating to time spans, due to the significance of the weekly cycle in our lives. This study claims that this behavior paradigm does not benefit investors. We further suggest that the Taiwanese government should abolish Article 165 of the Company Act, which requires that ＂the shareholders' roster shall not be altered within 5 days prior to the target date fixed by the issuing company for distribution of dividends.＂ This is to catch up with technological advancements in the modern world and for the benefit of investors.