Image via Wikipedia又是另外一個不求甚解, 嗚嗚嗚!!

80/20法則(80/20 rule)
也就是帕雷托法則(Pareto Principle)
News from: Wiki-帕雷托法則, Wiki-Pareto principle

帕雷托法則（Pareto principle），也稱為80/20法則，此法則指在眾多現象中，80%的結果取決於20%的原因，而這一法則在很多方面被廣泛的應用。如80%的勞動成果取決於20%的前期努力、20%的人做了80%的工作或者20%的維基人貢獻了80%的維基條目等等。但也常常被濫用、誤用，例如解決一個問題符合80/20法則，因為80%的問題由20%的資源來解決。

The Pareto principle (also known as the 80-20 rule, the law of the vital few and the principle of factor sparsity) states that, for many events, 80% of the effects comes from 20% of the causes. Business management thinker Joseph M. Juran suggested the principle and named it after Italian economist Vilfredo Pareto, who observed that 80% of income in Italy went to 20% of the population. It is a common rule of thumb in business; e.g., “80% of your sales comes from 20% of your clients."

Image via Wikipedia長尾理論(long Tail)
哀~ 讀書就是不求甚解, 被人問了, 知道有這樣一回事, 但是卻不知道該如何解釋

看過來吧!!
News from: Wiki-長尾, Wiki-The Long Tail

長尾（The Long Tail）一詞最初由Chris Anderson發表在2004年的《連線雜誌》[1]中， 用來描述諸如亞馬遜和Netflix Real.com Rhapsody 之類網站的商業和經濟模式。長尾這一術語也在統計學中被使用，通常應用在財產的分佈和詞彙的使用。

在亞馬遜這個案例上面，我們應用「長尾」概念可以解釋：它一半左右的銷售來自於比較熱門的商品，而另一半卻來自相對不那麼熱門的商品。這跟傳統的「二八定律」完全相反，所以這個概念的提出在Web2.0的時代顯得格外引人注目。

The phrase The Long Tail (as a proper noun with capitalized letters) was first coined by Chris Anderson in an October 2004 Wired magazine article [1] to describe the niche strategy of certain business such as Amazon.com or Netflix. The distribution and inventory costs of these businesses allow them to realize significant profit out of selling small volumes of hard-to-find items to many customers, instead of only selling large volumes of a reduced number of popular items. The group of persons that buy the hard-to-find or “non-hit" items is the customer demographic called the Long Tail.