圖書館裡找到的大師心法

多年前我城扑blog界曾掀起過一股出書潮，一眾扑bloggers都以網誌文章結集成書出版，美其名blook。魔術師當時也趁着人一世物一世的出版了生平的第一本書，叫做知道下出書是怎樣的一回事，長了經驗和知識，也算是趁機會感謝父母的養育教導之恩。
可幸的是，畢竟魔術師本書的文章都是由散文及短篇小說等拼湊而成，每一章節每一篇都可以獨立來看，內容即使較為鬆散也不成問題；不過如果係教學文章，以網誌輯錄而成的問題就較大，相信絕大部份博客寫文章不是以金庸式連載小說式發表，作為「教你ＸＸＸＸ法」的入門書籍，東講一忽西談一闕的問題就是連貫性不大，有幾多讀者可以跟隨到作者的思維頓成疑問。

魔術師近日好神心地去到圖書館借來本書，期望能從中學習大師秘技一二。可惜最後發現本書乃大師之扑文結集，而且本書疑團處處，艱深難解，即使出盡洪荒之力選擇文章閱讀，亦頗感困難，去到８０多頁，已難再進。相較之下，大師門生均視本書為寶典，閱之多遍，甚有所得，看來魔術師慧根實在甚差，無緣習得前輩神技，只得掩卷嘆息。

１. 買得抵唔等於買得中，有彩派。
２. ２０１０年話話企業可以「保留大部份每股盈利再投資，令到它的帳面值增大」，２０１６年卻說「可惜的是恆生指數或S&P500等的公司長期證明，保留盈利並沒有賺到它們數學計算的增長率」（見《拉三打四有害文》），大師的心真是難以捉摸。
３. 講到口臭，以低於價值的價格買入股票，即使「價值／價格回歸」，也不一定是價格上升，反映出價值，也可以是價值下跌，反映出價格。
４. 唔明「筆者」在32美元及28美元買入富國銀行，派息率表買入價計算起碼在８％，ＲＯＩ如何可以計到有１５％？「筆者」是否講緊入貨價比「筆者」要平上一半的股神的ＲＯＩ是１５％？
５. 既然市場錯價，中獎的機會大過1/36，但賠率卻又大過1/36，咁就要用 Kelly 來計算一下最合用的注碼，而唔係無厘頭地「加大自已在已經穩勝下敗仗的機會」：如果係「穩勝」，點解唔all-in？又要威又要戴頭盔，即係「可勝不穩」喇！

６. 書中的youtube link 已不復見：

不過憑前文後理，很可能所謂的「白鴿實驗」指的是Ｃ嬸和其他網友在《《海豚灣（The Cove）》：官商鄉黑處處有》中提及過的「白鴒大迷信」，似係「天狗食日」式的因果謬誤而唔係咩嘢病態賭徒心態：

Superstition in the pigeon[edit]
One of Skinner's experiments examined the formation of superstition in one of his favorite experimental animals, the pigeon. Skinner placed a series of hungry pigeons in a cage attached to an automatic mechanism that delivered food to the pigeon "at regular intervals with no reference whatsoever to the bird's behavior." He discovered that the pigeons associated the delivery of the food with whatever chance actions they had been performing as it was delivered, and that they subsequently continued to perform these same actions.[70]
One bird was conditioned to turn counter-clockwise about the cage, making two or three turns between reinforcements. Another repeatedly thrust its head into one of the upper corners of the cage. A third developed a 'tossing' response, as if placing its head beneath an invisible bar and lifting it repeatedly. Two birds developed a pendulum motion of the head and body, in which the head was extended forward and swung from right to left with a sharp movement followed by a somewhat slower return.[71][72]
Skinner suggested that the pigeons behaved as if they were influencing the automatic mechanism with their "rituals", and that this experiment shed light on human behavior:
The experiment might be said to demonstrate a sort of superstition. The bird behaves as if there were a causal relation between its behavior and the presentation of food, although such a relation is lacking. There are many analogies in human behavior. Rituals for changing one's fortune at cards are good examples. A few accidental connections between a ritual and favorable consequences suffice to set up and maintain the behavior in spite of many unreinforced instances. The bowler who has released a ball down the alley but continues to behave as if she were controlling it by twisting and turning her arm and shoulder is another case in point. These behaviors have, of course, no real effect upon one's luck or upon a ball half way down an alley, just as in the present case the food would appear as often if the pigeon did nothing—or, more strictly speaking, did something else.[71]
Modern behavioral psychologists have disputed Skinner's "superstition" explanation for the behaviors he recorded. Subsequent research (e.g. Staddon and Simmelhag, 1971), while finding similar behavior, failed to find support for Skinner's "adventitious reinforcement" explanation for it. By looking at the timing of different behaviors within the interval, Staddon and Simmelhag were able to distinguish two classes of behavior: the terminal response, which occurred in anticipation of food, and interim responses, that occurred earlier in the interfood interval and were rarely contiguous with food. Terminal responses seem to reflect classical (as opposed to operant) conditioning, rather than adventitious reinforcement, guided by a process like that observed in 1968 by Brown and Jenkins in their "autoshaping" procedures. The causation of interim activities (such as the schedule-induced polydipsia seen in a similar situation with rats) also cannot be traced to adventitious reinforcement and its details are still obscure (Staddon, 1977).[73]

７. 甚麼叫「賠賺８０／２０中的那２０」？是講賭錢嗎？之前唔係話唔應該有「賭徒心態」？嬴家得了輸家的錢？點解在「筆者」眼中的股票市場，忽然都變了賭場似的零和遊戲？
８. 魔術師在鄉大讀物理時，教授曾講述過如何可以簡易地驗證自己有無計錯數，其中一招就係「對單位」：例如你要計加速度，單位就係 m/s^2，分子係長度單位，分母係時間單位的二次方。以此觀之，股價的單位是「元」，資產、負債、盈利等的單位又是「元」，相乘之後如何可以劃上等號？就算「筆者」辯說這公式只是概念上的表達，而唔係真係相乘，依然係講唔通：點解係相乘唔係相加？２的Ｎ次方係「2x2x2x....x2」一共 N 次，看不出跟「筆者」的自創公式有何關係。再退一萬步想，大概「筆者」的意思是「估中某個因子」的機會率是 1/2，所以連續「估中」 N 個因子的機會率就是 1/2^N 了。但...乜大師心法就係教你靠估？
９. 呢一段的中文文法極差（又係讀得番薯多，以英文文法寫中文？）。退多一萬步想，甚麼「容錯度」，其實就係即使自己預計錯誤，都一樣可以「唔死得」的機會率，所以基本因素良好，有歷史的企業會較科網股之類的新興企業「穩陣」，即使計錯數都可以誤打誤墥唔死得而已。

１０. 又要睇返《拉三打四有害文》，乜「筆者」唔係話公司１００％派哂息俾佢就最好，因為「像筆者簡單地買入全派息ＸＸ，再投資回報率就肯定100%能按它的Yield%增長」咩？
１１. 其實魔術師已經忍住手，唔再批評佢呢段狗屁不通的中文。魔術師只係想話，「買入後股價跌了一半」，不等於是你「蠢」，但有可能代表你「計錯數」、或掌握唔到入市時機、或未有適當應對策略（止蝕也好、溝淡也好、無限補時都好，你都要有一個「理性解釋」，而唔係「主觀願望」）。至於是否「稱得上長期投資人」，先要看看有否「著重長期收益」，而唔係亂咁買，「升了就等於這隻蠢豬聰明」...呃，基本上魔術師是同意的，之不過係唔明點解「筆者」最近面對批評時要批評者先報上投資成績呢？如果對方是隻「亂咁買的蠢豬」，但回報卻要比「筆者」更好，那又叫「筆者」如何找下台階呢？
＊＊＊
睇到呢度，魔術師只覺本書textbook knowledge尚可，但「筆者」自創的演繹解說則不敢恭維，一係邏輯有誤，一係算式數目表違不清，「公式都搵唔到條，想扑嘢試演都唔得」，難以作深入理解，再者中文文法差劣，語意不清，錯別字頗多（魔術師最睇唔過眼的就係呢位「筆者」慣常將「多少」的「少」寫成「小」），基本上本書誤區跟其網誌可謂「一脈相承」；為免書評變扑評，都係就此打住，讓本書的命運跟大部份ＡＶ一樣，睇唔哂算了。
＊＊＊
伸延閱讀：
《海豚灣（The Cove）》：官商鄉黑處處有
黃Ｃ轉身
拉三打四有害文
賭神的注碼
＊＊＊
參考資料：
《大學沒有教的股票價值投資法》 羅健昌著 雅典娜策略有限公司出版 2014年5月第一次印刷