Does high frequency trading provide economic value?
"This is a very important question and you will find arguments from both sides, in part because it is still understudied. Ben Golub, Economics Ph.D., from Stanford answers ""Is high-frequency trading good for the economy?"" on Quoram quite well.  This is an important but understudied question. There are few   published academic studies on it, though several groups are working on   the subject. You may be interested in the following papers: http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1569067 http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1361184 These document some of the phenomena that arise in high frequency   trading, from a theoretical and an empirical perspective. However, a   full equilibrium analysis of the unique features of high frequency   trading is still missing, and until it is done, all our answers will   be kind of  tentative. Nevertheless, there are some obvious things one can say. Currently,   high frequency traders are competing to locate physically closer and   closer to exchanges, because milliseconds matter. Thus, large amounts   of money are being spent to beat other market makers by tiny fractions   of a second. Once many firms make these investments, the market looks   like it did before in terms of competition and prices, but is a tiny   bit faster. This investment is unlikely to be socially efficient: that   is, the users of  the market don't actually benefit from the fact that   their trades are executed half a millisecond faster -- certainly not   enough to cover all the investment that went into making that happen. Some people who study the issue believe that high frequency trading   (HFT) actually exacerbates market volatility; some plots to this   effect are found in the second paper linked above. There is certainly   no widely accepted theory that says faster trading technology   necessarily increases efficiency, and it is easy to think of   algorithms that can make money (at least in the short run) but hurt   most other investors, as well as the informational value of the   market. One caution is that some of the complaining about HFT comes from those   who lose when HFT gets better -- old-style market makers. They   certainly have an incentive to make HFT out to be very bad. So some   complaints about the predatory nature of HFT should be taken with a   grain of salt. There is no strong economic consensus about the value   of this activity. For what it's worth, my personal impression is that   this is more bad than good. I'll post an update here as more   definitive research comes out. You can also find a debate on High-frequency trading from the Economist which gives both sides of the argument. In conclusion: Regardless of how you feel about HFT it seems like it's here to stay and won't be leaving in the foreseeable future. So the debate will rage on... Additional resource you may finding interesting: Europe Begins Push To Ban HFT High Frequency Trading Discussion On CNBC Should High Frequency Trading (HFT) be banned ?" You pointed out that HFT does not create ipods are mine minerals.  Neither does human trading. HFT is a proxy for human trading.  Although the computer is executing trades automatically based on an algorithm, it is still using money from a human being's account so the trading is still being done with someone's money. Fast execution of trades is desirable in exchanges.  Imagine two exchanges:  One only executes trades once a month, the other executes trades once a week.  Which exchange would be more desirable?  The exchange that trades once a week.  Why?  Because if I'm holding a stock that I would like to sell, I want to sell it now - not a month from now.  Same reason for buying.  This concept works all the way down to seconds and fractions of seconds. The issue with HFT, however, is there are cases where the market goes against the HFT algorithm and the algorithm continues to execute trades driving prices up or down by large amounts in the matter of minutes or even seconds. The exchange frequently cancels these trades which only encourages more aggressive HFT trading since HFT traders can have their losses cancelled.  This is a privilege that LFTs (low frequency traders) do not receive.  This is a valid criticism of HFTs. A short list of such cancelled trades: 8/26/2010: Nasdaq cancels trades of CORE stock 10/4/2010: Nasdaq cancels trades of CENX stock 10/15/2010: NYSE cancels trades of PAY stock 10/18/2010: NYSE cancels $500 million worth of SPY trades 5/18/2011: NYSE cancels 15,900 trades of BEE.PR.C 6/21/2011: Nasdaq cancels CNTY trades 12/2/2011: London Metals Exchange cancel trades of copper
"An answer can be found in my book, ""A Modern Approach to Graham and Dodd Investing,"" p. 89 http://www.amazon.com/Modern-Approach-Graham-Investing-Finance/dp/0471584150/ref=sr_1_1?s=books&ie=UTF8&qid=1321628992&sr=1-1 ""If a company has no sustained cash flow over time, it has no value...If a company has positive cash flow but economic earnings are zero or less, it has a value less than book value and is a wasting asset. There is enough cash to pay interim dividends, bu the net present value of the dividend stream is less than book value."" A company with a stock trading below book value is believed to be ""impaired,"" perhaps because assets are overstated. Depending on the situation, it may or may not be a bankruptcy candidate." There are those who would suggest that due to the Efficient Market Hypothesis, stocks are always fairly valued. Consider, if non-professional posters on SE (here) had a method that worked beyond random chance, everyone seeking such a method would soon know it. If everyone used that method, it would lose its advantage. In theory, this is how stocks' values remain rational.  That said, Williams %R is one such indicator. It can be seen in action on Yahoo finance -  In the end, I find such indicators far less useful than the news itself. BP oil spill - Did anyone believe that such a huge oil company wouldn't recover from that disaster? It recovered by nearly doubling from its bottom after that news. A chart of NFLX (Netflix) offers a similar news disaster, and recovery.  Both of these examples are not quantifiable, in my opinion, just gut reactions. A quick look at the company and answer to one question - Do I feel this company will recover? To be candid - in the 08/09 crash, I felt that way about Ford and GM. Ford returned 10X from the bottom, GM went through bankruptcy. That observation suggests another question, i.e. where is the line drawn between 'investing' and 'gambling'? My answer is that buying one stock hoping for its recovery is gambling. Being able to do this for 5-10 stocks, or one every few months, is investing. "I think, the top three answers by Joe, Anthony and Bigh are giving you all the detail that you need on a technical sense. Although I would like to add a simple picture that underlines, that you can not really compare day trading to long-term trading and that the addictive and psychologic aspect that you mentioned can not be taken out of consideration. The long term investor is like someone buying a house for investment. You carefully look at all offers on the market. You choose by many factors, price, location, quality, environment, neighborhood and extras. After a long research, you pick your favorites and give them a closer look until you finally choose the object of desire, which will pay off in 10 years and will be a wise investment in your future. Now this sounds like a careful but smart person, who knows what he wants and has enough patience to have his earnings in the future. The short term investor is like someone running into the casino for a game of black-jack, roulette or poker. He is a person that thinks he has found the one and only formula, the philosopher's stone, the money-press and is seeking immense profits in just one night. And if it does not work, he is sure, that this was just bad coincidence and that his ""formula"" is correct and will work the next night. This person is a pure gambler and running the risk of becoming addicted. He is seeking quick and massive profits and does not give up, even though he knows, that the chances of becoming a millionaire in a casino are quite unrealistic and not better than playing in a lottery. So if you are a gamer, and the profit is less important than the ""fun"", then short term is the thing for you. If you are not necessarily seeking tons of millions, but just want to keep your risk of loss to a minimum, then long term is your way to go. So it is a question of personality, expectations and priorities. The answer why losses are bigger on high frequency signals is answered elsewhere. But I am convinced in reality it is a question of what you want and therefore very subjective. I have worked for both. I have worked for a portfolio company that has gone through periods of ups and downs, but on the long term has made a very tempting profit, which made me regret, that I did not ask for shares instead of money as payment. These people are very calm and intelligent people. They spend all their time investigating and searching for interesting objects for their portfolio and replace losers with winners. They are working for your money and investors just relax and wait. This has a very serious taste to it and I for my part would always prefer this form of investment. I have worked for an investment broker selling futures. I programmed the account management for their customers and in all those years I have only seen one customer that made the million. But tons of customers that had made huge losses. And this company was very emotional, harsh, unpersonal - employees changing day by day, top sellers coming in corvettes. All the people working there where gamblers, just like their customers. Well, it ended one day, when the police came and confiscated all computers from them, because customers have complained about their huge losses. I am glad, that I worked as a remote developer for them and got paid in money and not in options. So both worlds are so different from each other. The chances for bigger profits are higher on day trading, but so are the chances for bigger losses - so it is pure gambling. If you like gambling, split your investment: half in long term and other half in short term, that is fun and wise in one. But one thing is for sure: in over ten years, I have seen many customers loosing loads of money in options in the future markets or currencies. But I have never seen anyone making a loss in long term portfolio investment. There have been hard years, where the value dropped almost 30%, but that was caught up by the following years, so that the only risk was minimizing the profit." HFT is a controversial issue and there are smart people with very different opinions on it. You sound like your confidence in your own opinion is not matched with a deep knowledge of market structure.   Also, front running has a technical meaning, and what you are referring to as front running is something different. Don't like HFT? Use a stock exchange or dealer network that only allows manually entered trades.  I hope readers are not convinced by this article to support the enactment of regulations that prevent people from using HFT.  Maybe he's right and HFT is detrimental (which I doubt), but this is something that should be decided by the free market. "Not really. High frequency traders affect mainly short term investors. If everyone invested long-term and traded infrequently, there would be no high frequency trading. For a long term investor, you by at X, hold for several years, and sell at Y. At worst, high frequency trading may affect ""X"" and ""Y"" by a few pennies (and the changes may cancel out). For a long term trader that doesn't amount to a ""hill of beans"" It is other frequent traders that will feel the loss of those ""pennies.""" "Maria, there are a few questions I think you must consider when considering this problem. Do fundamental or technical strategies provide meaningful information? Are the signals they produce actionable? In my experience, and many quantitative traders will probably say similar things, technical analysis is unlikely to provide anything meaningful. Of course you may find phenomena when looking back on data and a particular indicator, but this is often after the fact. One cannot action-ably trade these observations. On the other hand, it does seem that fundamentals can play a crucial role in the overall (typically long run) dynamics of stock movement. Here are two examples, Technical: suppose we follow stock X and buy every time the price crosses above the 30 day moving average. There is one obvious issue with this strategy - why does this signal have significance? If the method is designed arbitrarily then the answer is that it does not have significance. Moreover, much of the research supports that stocks move close to a geometric brownian motion with jumps. This supports the implication that the system is meaningless - if the probability of up or down is always close to 50/50 then why would an average based on the price be predictive? Fundamental: Suppose we buy stocks with the best P/E ratios (defined by some cutoff). This makes sense from a logical perspective and may have some long run merit. However, there is always a chance that an internal blowup or some macro event creates a large loss.  A blended approach: for sake of balance perhaps we consider fundamentals as a good long-term indication of growth (what quants might call drift). We then restrict ourselves to equities in a particular index - say the S&P500. We compare the growth of these stocks vs. their P/E ratios and possibly do some regression. A natural strategy would be to sell those which have exceeded the expected return given the P/E ratio and buy those which have underperformed. Since all equities we are considering are in the same index, they are most likely somewhat correlated (especially when traded in baskets). If we sell 10 equities that are deemed ""too high"" and buy 10 which are ""too low"" we will be taking a neutral position and betting on convergence of the spread to the market average growth. We have this constructed a hedged position using a fundamental metric (and some helpful statistics). This method can be categorized as a type of index arbitrage and is done (roughly) in a similar fashion. If you dig through some data (yahoo finance is great) over the past 5 years on just the S&P500 I'm sure you'll find plenty of signals (and perhaps profitable if you calibrate with specific numbers). Sorry for the long and rambling style but I wanted to hit a few key points and show a clever methods of using fundamentals." In the short term the market is a popularity contest In the short run which in value investing time can extend even to many years, an equity is subject to the vicissitudes of the whims by every scale of panic and elation. This can be seen by examining the daily chart of any large cap equity in the US.  Even such large holdings can be affected by any set of fear and greed in the market and in the subset of traders trading the equity. Quantitatively, this statement means that equities experience high variance in the short rurn. in the long term [the stock market] is a weighing machine In the long run which in value investing time can extend to even multiple decades, an equity is more or less subject only to the variance of the underlying value. This can be seen by examining the annual chart of even the smallest cap equities over decades.  An equity over such time periods is almost exclusively affected by its changes in value. Quantitatively, this statement means that equities experience low variance in the long run. No. The long-term valuation of currencies has to do with Purchasing Power Parity.  The long-term valuation of stocks has to do with revenues, expenses, market sizes, growth rates, and interest rates. In the short term, currency and stock prices change for many reasons, including interest rate changes, demand for goods and services, asset price changes, political fears, and momentum investing.  In any given time window, a currency or stock might be: The Relative Strength Index tries to say whether a currency or stock has recently been rising or falling; it does not inherently say anything about whether the current value is high or low. In my experience thanks to algorithmic trading the variation of the spread and the range of trading straight after a major data release will be as random as possible, since we live in an age that if some pattern existed at these times HFT firms would take out any opportunity within nanoseconds. Remember that some firms write algorithms to predict other algorithms, and it is at times like those that this strategy would be most effective. With regards to my own trading experience I have seen orders fill almost €400 per contract outside of the quoted range, but this is only in the most volatile market conditions. Generally speaking, event investing around numbers like these are only for top wall street firms that can use co-location servers and get a ping time to the exchange of less than 5ms. Also, after a data release the market can surge/plummet in either direction, only to recover almost instantly and take out any stops that were in its path. So generally, I would say that slippage is extremely unpredictable in these cases( because it is an advantage to HFT firms to make it so ) and stop-loss orders will only provide limited protection. There is stop-limit orders( which allow you to specify a price limit that is acceptable ) on some markets and as far as I know InteractiveBrokers provide a guaranteed stop-loss fill( For a price of course ) that could be worth looking at, personally I dont use IB.  I hope this answer provides some helpful information, and generally speaking, super-short term investing is for algorithms. "Are you talking long-term institutional or retail investors? Long-term *retail* investors look for *orderly markets*, the antithesis of HFT business models, which have a direct correlation between market volatility and profits. To a lesser extent, some ""dumb money""/""muppet"" institutionals do as well. HFT firms tout they supply liquidity into markets, when in fact the opposite is true.  Yes, HFTs supply liquidity, *but only when the liquidity's benefits runs in their direction*. That is, they are applying the part of the liquidity definition that mentions ""high trading activity"", and conveniently ignoring the part that simultaneously requires ""*easily* buying *or* selling an asset"".  If HFT's are the new exchange floor, then they need to be formalized as such, *and become bound to market maker responsibilities*. If they are actually supplying liquidity, like real Designated Market Makers in the NYSE for example, they become responsible to supply a specified liquidity for specified ticker symbols in exchange for their informational advantage on those tickers. The indisputable fact is that HFT cannot exist at their current profit levels without the information advantage they gain with preferential access to tick-by-tick data unavailable to investors who cannot afford the exchange fees ($1M per exchange 10 years ago, more now). Restrict the entire market, including HFTs, to only second-by-second price data without the tick-by-tick depth, and they won't do so well.  Don't get me wrong, I'm not knocking HFTs *per se*; I think they are a marvelous development, so long as they really do ""supply liquidity"". Right now, they aren't doing so, and especially in an orderly manner. If you want retail investors to keep out of the water as they are doing now, by all means let HFT (and regulatory capture, and a whole host of other financial service industry ills) run as they are. There are arguments to be made about ""only let the professionals play the market"", where there is no role for retail and anyone who doesn't know how to play the long-term investment game needs to get out of the kitchen. But if you are making such an argument, come out and say so." Yes, but it must be remembered that these conditions only last for instants, and that's why only HFTs can take advantage of this. During 2/28/14's selloff from the invasion of Ukraine, many times, there were moments where there was overwhelming liquidity on the bid relative to the ask, but the price continued to drop. The stock market's principal justification is matching investors with investment opportunities.  That's only reasonably feasible with long-term investments.  High frequency traders are not interested in investments, they are interested in buying cheap and selling expensive.  Holding reasonably robust shares for longer binds their capital which is one reason the faster-paced business of dealing with options is popular instead.  So their main manner of operation is leeching off actually occuring investments by letting the investors pay more than the recipients of the investments receive. By now, the majority of stock market business is indirect and tries guessing where the money goes rather than where the business goes. For one thing, this leads to the stock market's evaluations being largely inflated over the actual underlying committed deals happening.  And as the commitment to an investment becomes rare, the market becomes more volatile and instable: it's money running in circles. Fast trading is about running in front of where the money goes, anticipating the market.  But if there is no actual market to anticipate, only people running before the imagination of other people running before money, the net payout converges to zero as the ratio of serious actual investments in tangible targets declines. By and large, high frequency trading converges to a Ponzi scheme, and you try being among the winners of such a scheme.  But there are a whole lot of people competing here, and essentially the net payoff is close to zero due to the large volumes in circulation as opposed to what ends up in actual tangible investments. It's a completely different game with different rules riding on the original idea of a stock market.  So you have to figure out what your money should be doing according to your plans. &gt; Stock markets are supposed to be about investment and providing capital to companies for operations and research. High frequency trading is only about gaming the market and nothing else. Arguments that this provides more capital or liquidity don't make any sense because the speed of trading is such that listed companies cannot take advantage and only high frequency traders are served.  I used to feel this way about derivatives but a commentator on reddit disabused me of that notion -   http://www.reddit.com/r/Entrepreneur/comments/11bqnk/what_you_wont_see_on_the_front_page_of_reddit_the/c6lnqow  If the only function of the stock market is investment and provide capital to companies, why have a secondary market at all? &gt; I no longer have the fantasy belief that I can do better managing my money than professional investors  The pension fund probably lost about as much as your investments did, but they still had to pay out as if they were meeting their targets. I understand you weren't really offered a choice between a higher salary or a pension, so my observation is academic, but to me it just seems strange to believe that a company can pay you a fixed sum of money 30 years in the future.   Maybe it's just a generational thing but the whole idea of investing (figuratively) your entire future in a single company doesn't make sense to me. I actually think it's good in the long run that we're moving away from the work at one company your entire life model. Companies shouldn't be in the business of providing retirement benefits any more than they should healthcare plans, IMO.