7月第22天
昨日阅读5小时,累计阅读366小时
1.今天你阅读到的有价值的全文内容链接
推荐: 《数值分析》(第七版 中文翻译版)
By:Richard L. Burden & J. Douglas Faires
4B,还算比较值!
https://bbs.pinggu.org/thread-5330885-1-1.html
2.今天你阅读到的有价值的内容段落摘录
今天继续读:《Definitive Guide to Position Sizing》:Chapter 2
Risk(R) and R-Multiples (beginning)
……
Chapter 2
Risk(R) and R-Multiples
Let’s look at the first golden rule in much more detail to be sure that you understand it. That rule, if you remember it, is to always have an exit point when you enter a position. The prupose of that exit point is to help you preserve your trading/investing capital.  And that exit point defines your initial risk in a trade.
Wall Street defines the risk in a trade by its potential volatility: how much you can expect your account ( or that position ) to fluctuate. However, that’s not the definition fo risk that we’ll use here. Here risk is defined as how much you’ll lose per unit of your investment (i.e., share of stock or number of futures contracts ) if you are wrong about the position. I call this initial Risk ( R or 1R ). And the good news is that you can contral this form of risk.
Let’s look at some examples:
        Example 1: You buy a cstock at 50 and decide to sell it if it drops to 40. What’s your initial risk?
        The initial risk is 10 per share. So in this case, 1R is equal to 10. If you buy 100 shares, then your total risk is 1000 (i.e., 10x100). But let’s call R our risk per unit.
        Example 2: You buy the same stock at 50, but decide that you are wrong about the trade if it drops to 49. At 49 you’ll get out.  What’s yur initial risk?
        In the second example, your initial risk is 2 per share, so 1R is equal to 2.  Notice that each time you buy a 50 stock, but in the two cases you are simply selecting different initial risks or R values.
        Example 3: You buy a stock for 24 and you decide to keep a 25% trailing stop. That means you’ll sell if it drops 25% from the entry price or from any subsequent higher closing price the stock makes. What’s your initial risk?  What’s 1R for you?
        In the third example, you’d sell the stock if it drops 25% to 19. Thus, your initial risk is 6/share and 1R is equal to 6.
        Example 4: You have a soybean contract at 5.20 per bushel. You decide to sell if it drops 10 centx. What’s your initial risk per contract given that one contract is 5,000 bushels? What’s 1R for you?
        In this case, you multiply 5,000 by your loss per bushel of 10 cents. Your initial risk is 500, so 1R is 500 per contract.
        Example 5: You want to do a foreign exchange trade with a 10,000 account, buying the dollar against the euro. Let’s say that 100 USD is equal to 77 Euros. The minimum unit you must invest is 10,000. You are going to sell if your investment drops by 1,000.  What’s your risk? What’s 1R for you?
        I made this example sound complex, but is isn’t. If your minimum investment is 10,000 and you’d sell if it dropped $1,000 to 9,000, then your initial risk is 1,000, and 1R is 1,000.
Are you beginning to understand? R represents your initial risk per unit.  It’s not your total risk in the position because you might have multiple units ---- it’s simply the initial risk per share of stock or per futures contract or per minimum investment unit.
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3.今天你阅读到的有价值信息的自我思考点评感想
        决策,投资决策的根本是什么?尤其是购买股票决策的真正根本是什么?是风险,而不是一般意义上的收益:收益不需要决策。我打算冒多大的风险来购买这支股票?
        R乘数告诉我们,这样来思考进行的决策才是我们在交易中取得盈利的根本:在购买的时候就已经决定了我们所能承担的风险是具体什么样的,价值多少。
         通过5个具体例子来了解最基本的R乘数的定义,印象深刻。这和我之前所具有的信念(我还不清楚是从哪里来的这样的信念)完全不同。震撼人心!