Accepting high volatility for high long-term returns
"This is basically what financial advisers have been saying for years...that you should invest in higher risk securities when you are young and lower risk securities when you get older. However, despite the fact that this is taken as truth by so many financial professionals, financial economists have been unable to formulate a coherent theory that supports it.  By changing the preferences of their theoretical investors, they can get solutions like putting all your investments in a super safe asset until you get to a minimum survival level for retirement and then investing aggressively and many other solutions.  But for none of the typically assumed preferences does investing aggressively when young and becoming more conservative as you near retirement seem to be the solution.  I'm not saying there can be no such preferences, but the difficulty in finding them makes me think maybe this idea is not actually correct. Couple of problems with your intuition that you should think about: It's not clear that things ""average out"" over time.  If you lose a bunch of money in some asset, there's no reason to think that by holding that asset for a while you will make back what you lost--prices are not cyclical.  Moreover, doesn't your intuition implicitly suggest that you should transition out of risky securities as you get older...perhaps after having lost money? You can invest in safe assets (or even better, the tangency portfolio from your graph) and then lever up if you do want higher risk/return.  You don't need to change your allocation to risky assets (and it is suboptimal to do so--you want to move along the CAL, not the curve). The riskiness of your portfolio should generally coincide (negatively) with your risk-aversion.  When you are older and more certain about your life expectancy and your assets, are you exposed to more or less risks?  In many cases, less risks.  This means you would choose a more risky portfolio (because you are more sure you will have enough to live on until death even if your portfolio takes a dive). Your actual portfolio consists both of your investments and your human capital (the present value of your time and skills).  When you are young, the value of this capital changes significantly with market performance so you already have background risk.  Buying risky securities adds to that risk.  When you are old, your human capital is worth little, so your overall portfolio becomes less risky.  You might want to compensate by increasing the risk of your investments. EDIT: Note that this point may depend on how risky your human capital is (how likely it is that your wage or job prospects will change with the economy). Overall the answer to your question is not definitively known, but there is theoretical evidence that investing in risky securities when young isn't optimal. Having said that, most people do seem to invest in riskier securities when young and safer when they are older. I suspect this is because with life experience people become less optimistic as they get older, not because it is optimal to do so.  But I can't be sure." Modern portfolio theory has a strong theoretical background and its conclusions on the risk/return trade-off have a lot of good supporting evidence.  However, the conclusions it draws need to be used very carefully when thinking about retirement investing.  If you were really just trying to just pick the one investment that you would guess would make you the most money in the future then yes, given no other information, the riskiest asset would be the best one.   However, for most people the goal retirement investing is to be as sure as possible to retire comfortably.  If you were to just invest in a single, very risky asset you may have the highest expected return, but the risk involved would mean there might be a good chance you money may not be there when you need it. Instead, a broad diversified basket of riskier and safer assets leaning more toward the riskier investments when younger and the safer assets when you get closer to retirement tends to be a better fit with most people's retirement goals.  This tends to give (on average) more return when you are young and can better deal with the risk, but dials back the risk later in life when your investment portfolio is a majority of your wealth and you can least afford any major swings.  This combines the lessons of MPT (diversity, risk/return trade-off) in a clearer way with common goals of retirement. Caveat:  Your retirement goals and risk-tolerance may be very different from other peoples'.  It is often good to talk to (fee-only) financial planner. "Modern portfolio theory dramatically underestimates the risk of the recommended assets.  This is because so few underlying assets are in the recommended part of the curve.  As investors identify such assets, large amounts of money are invested in them.  This temporarily reduces measured risk, and temporarily increases measured return.  Sooner or later, ""the trade"" becomes ""crowded"".  Eventually, large amounts of money try to ""exit the trade"" (into cash or the next discovered asset).  And so the measurable risk suddenly rises, and the measured return drops. In other words, modern portfolio theory causes bubbles, and causes those bubbles to pop. Some other strategies to consider:"
Your mortgage represents a negative cash flow of $X for N months. The typical mortgage prepayment doesn't reduce your next payment, but does reduce the length of the mortgage. If you look at the amortization table of a 30 year loan, you might see a payment of $1000 but only $50 going to principal. So if on day one you send an extra $51 or so to the bank, you find that in 30 years you just saved that $1000 payment. In effect, it was a long term bond or CD, yielding the post tax rate of the mortgage. Say your loan were 7%. At 7%, money doubles every 10 years or so. 30 years is 3 doubles or 8X. If I were to offer you $1000 and ask for $7500 in 30 years, you might accept it, with an agreement to buy me out if you refinanced. For me, that would be an investment. Just like buying a bond. In fact, there is a real return, as you see the cash flow at the end. The payments 'not made' are your payback.  Those who insist it's not an investment are correct in the strict sense of the word's definition, but pedantic for the fact in practice, the prepayment is a choice to be considered alongside other investment choices. When I have a mortgage, I am the mortgagor, the bank, the mortgagee. Same as a company issuing a bond, the Bank holds my bond and I'm making payments to them. They hold my bond as an investment. There is no question of that. In fact, they package these and sell them as CMOs, groups of mortgages. A pre-payment is me buying back the last coupon on my mortgage. I fail to see the distinction between me 'buying back' $10K in future coupons on my own loan or me investing $10K in someone else's loans.  The real question for me is whether this makes sense when rates are so low. At 4%, I'd say it's a matter of prioritizing any high rate debt and any other investments that might yield more. But even so, it's an investment yielding 4%.  Over the years, I've developed the priorities of where to put new money - The priorities are debatable. I have my opinion, and my reasons to back them up. In general, it's a balance between risk and return. In my opinion, there's something wrong with ignoring a dollar for dollar match on the 401(k) in most circumstances. Others seem to prefer being 100% debt free before saving at all. There's a balance that might be different for each individual. As I started, the mortgage is a fixed return, with no chance to just get it back if needed. If your cash savings is pretty high, and the choice is a .001% CD or prepay a 4% mortgage, I'd use some funds to pay it down. But not to the point you have no liquid reserves. Algorithmic trading essentially banks on the fact that a price will fluctuate in tiny amounts over short periods of time, meaning the volatility is high in that given time frame. As the time frame increases the efficiency of algorithmic trading decreases and proper investment strategies such as due diligence, stock screening, and technical analysis become the more efficient methods.  Algorithms become less effective as the time frame increases due to the smoothing effect of volatility over time. Writing an algorithm that could predict future long-term prices would be an impossible feat because as the time frame is scaled up there are far less price fluctuations and trends (volatility smooths out) and so there is little to no benchmark for the formulas.  An algorithm simply wouldn't make sense for a long-term position. A computer can't predict, say, the next quarter, an ousted CEO, a buyout, or anything else that could effect the price of the security, never mind the psychology behind it all. Vice versa, researching a company's fundamentals just to bank on a 0.25% daily swing would not be efficient. Tax advantages or not, it is the most efficient methods that are preferred for a given time-scale of trading. With the netural position delta strategy under high IV returns short vega,there is a possibility to profit from a decline in IV. Of course, if volatility rises higher, the position will lose money. It is therefore best to establish short vega delta-neutral positions when implied volatility is at levels that are in the 90th percentile ranking. You won't hear me calling crypto a safe haven as such. The local price volatility is more than most people can handle. And it takes a level of tech savvy to be able to separate facts from nonsense.  By my personal analysis, Ethereum (ETH) would be the safest crypto investment by far. Bitcoin (BTC) is also surprisingly resilient in terms of value, but has been deprecated on multiple levels at this point, so it seems quite overvalued (or Ethereum undervalued for that matter). The rest of crypto can probably best be compared to investing in startups. High risk, high reward. "A minor tangent. One can claim the S&P has a mean return of say 10%, and standard deviation of say 14% or so, but when you run with that, you find that the actual returns aren't such a great fit to the standard bell curve. Market anomalies producing the ""100-year flood"" far more often than predicted over even a 20 year period. This just means that the model doesn't reflect reality at the tails, even if the +/- 2 standard deviations look pretty. This goes for the Black-Sholes (I almost abbreviated it to initials, then thought better, I actually like the model) as well. The distinction between American and European is small enough that the precision of the model is wider than the difference of these two option styles. I believe if you look at the model and actual pricing, you can determine the volatility of a given stock by using prices around the strike price, but when you then model the well out of money options, you often find the market creating its own valuation." My thoughts from the top:  1. If you're already long, which not just buy-write? if you want to sit on the portfolio for some time with little rebalancing collecting some option premiums might not be bad?  2. You can replicate this portfolio on a rolling basis through bull spreads, which should hedge (or at least reduce) your theta and give you some of that sweet sweet convexity, however you will need a large enough size to cover your transaction costs.  3. I agree with maximizing mean / lower semi var (most kids max mean/var)) so good move there. However you need estimates of expected return (not easy!) and semi var (easier). Look into using GARCH (or a form of it) on the semi var for a better estimator.  4. Is this an MSR portfolio? How do you determine your weights?  5. In terms of sizing/leverage,  Remember the betting condition that equity needs to be positive for all time. How are you planning to limit your max DD? and how often do you plan on rebalancing/rebetting. It has been hinted at in some other answers, but I want to say it explicitly: Volatility is not risk. Volatility is how much an investment goes up and down, risk is the chance that you will lose money. For example, stocks have relatively high volatility, but the risk that you will lose money over a 40 year period is virtually zero (in particular if you invest in index funds). Bonds, on the other hand, have basically no volatility (their cash flow is totally predictable if you trust the future of your government), but there is a significant risk that they will perform worse than stocks over a longer period. So, volatility equals risk only if you are day trading. A 401(k) is literally the opposite of that. For further reading: Never confuse risk and volatility Also, investing is not gambling. Gambling is bad because the odds are stacked against you. You need more than average luck to actually win and the longer you play, the more you will lose. Investing means buying productive capital that will produce further value. The odds are in your favor. Even if you do a moderately bad job at investing, the longer you stay, the more you will win. "If by saying you wish to invest ""for the long term 5-10 years"" I take it you mean to hold a stock for between 5-10 years. If this is the case, this is the fundamental flaw in your screening algorithm. No company stock price continues to go up without end for 5-10 years. The price of every company's stock goes down at some point. You have to decide on a company by company basis whether you want to ride out the downturn or sell and get out. This is a personal decision based on your own research. The list of screening criteria you list indicates you are looking for solid earnings companies. Try not to apply these rules rigidly because every company runs through a rough patch. At times past, GE (for example) met all of your criteria. However, in 2017, it would not and therefore would not meet your screening criteria. Would you sell GE if you owned it? Maybe, or maybe you would hold through the downturn. The same be said for MSFT in 2010 or AAPL pre-Jobs return. A rule you may want to add to your list: know the company business well; that is, don't invest in companies you have no understanding of their business model."