is also not easy. In the past 6 months, US market rised almost 30%.. This means every month you have to buy 5% higher on the price, sounds scared? yes, probably not even wise if your trading horizon is less than a year. However, if you are talking about 15 years or 20 years investment time frame, This is just part of your game plan. It is the DISCIPLINE.

While on the other side, some people also talk about sell high first then buy lower. They are not wrong neither, provided their trading time frame is in week or even days. Everyone has different personality, different belief, different knowledge and background, different time they can spend to watch the market. The importance is to align the strategy consistently into your character and life.

Both long term investment and short term speculation can lead to big win or loss. The difficult part in fact is not on the perception, but execution.

Let me explain why it is so.

warren Buffett has a lot sayings. But one of his statement is like this:" the biggest edge as a retail investor is the "size". If you give me $1million, I can easily achieve 100% or even higher return. but if it is $20million, the return may be dramatically reduced."

For US market, except for those very illiquid stocks, a 6- figure or even low-end 7 figures US dollar market order could be easily absorbed within a second. This is exactly the 'edge' for the retail investor, because a retail participant can get in and out of a stock at whatever price with desired quantity within split second. However, the story is totally different for FUND. A fund has a lot rules and constraints. The set of the rules specify minimum market cap of the stocks they can purchase, minimum holding period, maximum shareholdings, a necessary liquidation (cut loss)requirement, and many others. Therefore, there is a natural tendency that most of the funds have to shift their focus to mid cap or big cap stocks (the fantasy 7 for example) due to liquidity constraint, and obviously most of their FUND performance is just a replication of SP500 or nasdaq100 index.

all great companies evolved from 30m-50m small cap company in the first few years, and those were the fastest growing period in their financials. If one has spare time and money to do stock selection on his own or just simply wants to challenge himself, then why not, just do it. But for many who have a full day job, index fund is still a good choice.

The index performance definitely is not y=x type of trend.
Take the oldest Dow jones index for example:

1) from 1929 - 1954, it took almost 25 years to recover the financial crisis top 380
2) from 1966 - 1982, the market just went nowhere but sideways between 800 - 1000 for 16 years
3) from 2000 - 2010, the tech bubble and sub-prime crisis has made the market wild oscillating between 8000 - 14000

What I mean is sometimes in our life we need some luck. This is especially true in investing (speculating). Imagine you are living between 40s - 60s in those period and you have to force sell your stocks for your retirement at the market extremely low. It might happen. nothing is 100%. It is just that probability wise market has a good chance(as for past 100 over years, always) to recover. The question is "how long". Japan, another mega economy, took almost 35 years to recover its 1990 peak 39000 this Feb. and China...no comment

To make a fortune, have to plan first, take a risk, and hope for the best.

dollar cost averaging 只是无数种投资逻辑中的一种，只要选对标的，它可能在漫长的投资周期中让投资者能跑赢通胀。但它绝对不是市场中唯一的圣杯呀。。。你想市场中有那么多的参与者，hedgers, arbitragers, long term investors, short term traders, High frequency algorithm trading, etc..... 无论哪种都有赚钱的，赔钱的，赚大钱的，赔大钱的。多听听别人说的有好处。。即使你觉得人家方法很幼稚或者错误，那不也是免费学习避雷了嘛。。

只要时间够久，dollar cost averaging 的胜率就越大。不走运的事肯定也会有发生的概率，比如在65岁需要卖股换钱的时候市场真的跌到了最低点。以前我也列举过美国至少有3个超过10年以上的周期是不涨或者下跌很久的例子。但只要不卖在最低点， dollar cost averaging 不会让人亏太多，毕竟还有分红，但也不会给出很可观的超额回报,。所以从这个角度说，dollar cost averaging算是偏保守的策略了。

because we were, we are and we will be human, no matter when. Even AI or algorithem trading are designed by human.

because no two events, patterns, triggers are exactly the same. it should be rather a statistical or experiential affair than an exact science. so in this sense you are damn right. I would say "belief make it happen". We just try to do what we "believe" :)

只要想参与市场的人谁都躲不掉。咱们要做的就是劲量避免个股黑天鹅，能少中招就算很成功了

什么情况出，卖多少。遇到紧急事件有没有预案，等等。。。这些都想好的话，这笔投资或者交易无论赚与赔，都是一个“好”字。没想好这些的话，那就是翻硬币了。 discipline is the key.

其实就是无穷杠杆，也挺坑人。交易所其实应该把这样的规则改掉才好。。

微软会被连带索赔吗？有啥明确的这种软件失能需要赔偿的法律依据吗？

所以在新的entry $430这个位置你的计划是什么？ 为什么买$430这个价格？要持股几天（从你卖460买430我猜你是按天算）？目标价位还是原来的双头$460-$470吗？如果下个周一经过长周末gap down 比如开在$427怎么应对？如果MSFT如你所愿真的反弹到$455但是差点到$460就又下来了，出吗？还是这些都不重要，走一步看一步？

统计学，或者金融学的博士才能买卖，而是对于普罗大众只要具备正常的智商，一定的初始资金就可以买卖。但这并不是说没有门槛，最基本的必要的知识还是要掌握，否则100%没法生存。"dollar cost averaging" 这个名词第一次出现应该是在巴菲特的老师 Benjamin Graham 的 "the intelligent investor" 的书里。他明确定义了“Dollar cost averaging means simply that the practitioner invests in common stocks the same number of dollars each month or each quarter . 这里他说的common stock 指的应该不是个股，而是广义的broader market. 同时他明确得指出了 dollar cost averaging 是一种 “formula investing”, 或者说" algorithm investing"

每个人都有自己不同的投资风格，但是这并不妨碍我们了解其它各种理念。我们可以赞同，也可以不赞同。赞同就汲取，不赞同就理性客观的指出你认为的逻辑不足之处就好了。我觉得交易是个性化的艺术，没有对错。诚然在交易世界我们总是以结果论英雄，但对于投资或者交易，有时即使逻辑或者系统有正预期回报，运气或者执行力不好，也是会赔钱的。

因为大家会比较自然地把目光放在average上，但其实不是真的average, 比如每个月投$100, 假设今天价格是10$, 所以买了10股，下个月同一天比如价格涨了10倍，到了$100, 按照原则只能买1股， 所以两个月的成本是$18.1。 再加上dividend reinvest， 长期是一个巨大的复利，这应该就是dollar cost averaging 这个策略的本意。 在历史上以20年为一个周期，dollar cost averaging只有1929大萧条跌90%和日本20年跌80%的那2-3年，如果投资者卖到了最低点才是赔钱的，其他任何时间剔除inflation都是赚的。

但毕竟它还是一个很保守的策略，而且20年的周期没有回头路，投了好几年下车也很困难，中间再经历大大小小的振幅，绝对是对人性很大的考验。。

我想了想这样的操作还是要小心一点，因为在市场一直温和健康上涨的情况下这样肯定能把收益提高不少，但是同样这也意味着在高位没有投入同样的 dollar amount. 没人能100%确定这个5%或者10%的回调是一个正常上涨趋势中的回调还是猛烈下跌的第一波， 如果是后者这样加码就会变成高位加仓，违背了dollar cost averaging的本意，你可以再考虑一下

而 DCA 更多的时候是在average up.... 金融从业人员如果真的咬文嚼字起来还是要更严谨啊。。。