Originally posted by Magna
dottom,
My system executed a buy signal on the opening bar
The opening bar of what? Without revealing proprietary info, would you mind talking around a system that signaled a buy on the opening bar of a day like today. Thanks.
Without going into details of my precise trading system, I have no problems talking about some of its components, which may give others ideas on how I approach the markets.
First, when I said opening bar it means an order was filled on the opening bar of whatever time frame I'm following. I use both a short-term and long-term time frame, primarily 3m, 30m, and 60m bars. The market is S&P futures, where many system traders go mining for gold.
Ok, here are the main components that intersected to generate a buy signal. A robust system will several different components, and an entry or exit signal is generated with specific combinations. A lot of book pushers talk about looking at the markets "in 3D" or using confirming indicators or "triple screens" etc. This is basically the same thing but I believe my techniques are much more robust than those book pushers.
To follow my analysis you will need to look at a 30m and 60m SP01Z chart.
[1] Pre-entry component: First thing I do before the market trades is look at where S&P's are going to open. This easy just look at the Globex session. If the market is going to gap open above or below yesterday's range then I require a different set of signals to generate a trade than if the market were to open within the range of yesterday's high-low.
[2] Pre-entry component: My system is always aware of support/resistance. Specifically, I look at 30m and 60m bars for support & resistance. There is no subjectivity here, I use a simple highest-high and lowest-low period to determine support & resistance. If prices behave a certain way X% above support, that is a bullish signal. If prices breaks through support that is a bearish signal. Notice that Wednesday's low was significant support, tested several times in past week, and also the top of the opening gap on 11/13. If you don't believe that S/R can help you increase risk/reward then you can stop reading right here.
[3] Pre-entry component: Run a statistical test on this RSI(5). Take 60m bars. Now look at all the times that the RSI(5) <20 or >80. For every time that the RSI(5) stayed <20 or >80 for 3+ bars, after RSI(5) is no longer <20 or >80, look at what % of the time price will move above the highest high of first RSI(5) bar <20; or below lowest low of first RSI(5) bar >80. Look 7-14 bars after the RSI is no longer overbought/oversold. I used 7-14 because 7 is one full trading day. No optimization here, you can use different RSI period or different lookahead period, the point is to look at what
tendency prices have after this happens. Some people fashion enter trading systems around just the RSI and an MA. I haven't had much success with a specific use of an RSI, but here I use it as a general signal. If I told you that you had a X% chance the price would be higher Y% in the next Z bars you could make trade with statistical probability in your favor. In the worse case, if this is just coincidence, it's 50/50 anyways, but I believe it is not coincidence. Simply put, after 3+ consecutive oversold RSI bars, price will have a much higher probability to trade above the first RSI bar than below it the next 1-2 days. Vice-versa for overbought. The reason that this probability is important is because it is a confirming pre-market bullish indicator. Also, if I know that price has a higher probability to move higher in next 1-2 days, it is more likely that I won't get stopped out, and within a few bars I could move my stops to break-even. Combine this with [2] and you have a bullish bias. Now define your trigger.
[4] Pre-entry component/trigger: One of my triggers is if prices had a channel breakout above highest-high of recent highs. (I also use limit order triggers to buy dips & sell rallies, but this case is a breakout trigger.) Both 30m and 60m bars broke through the current congestion. I would be long here on either 30m or 60m chart. Sell stop would be below support which was yesterday's low. This breakout is made even more significant in that it happened above major support [1] and within Z period and X% of [2]. (e.g. try looking at a pure breakout system, but instead of taking every signal, you only look at what filters you can to improve results).
[5] Post-entry confirmation: I use a 40-period MA as a post-entry confirming indicator. I don't use it to directly enter or exit trades, but to confirm whether I should HOLD or EXIT. A lot of people exit only when the market this their stop price. Don't let the market prove you wrong, let the market prove you right! If the market doesn't confirm my signal I exit at market. Most systems I've seen are in the market too often. I only enter when conditions are right and sit on the sidelines when they are not (I thought today's low holiday volume would be one of those, that was a discretionary decision). This reduces risk and also reduces capital requirements for following multiple markets (e.g. diversification with less capital). Also note that depending on which type of MA you use, it would have crossed the MA to the upside on the first or second bar on both 30m and 60m charts. Some people test a very specific combination of SMA's, EMA's, AMA's, JMA's etc. My trick with MA's is to make sure that if you vary your period or type of MA the general behavior is the same. Do not curve fit!
[6] Post-entry confirmation: Similar to how [3] is a confirming indicator once in a trade, another post-entry confirming indicator is when the same RSI(5) moves in the direction of my trade. I want the RSI to be overbought when I'm long or oversold when I'm short. Look at both 30m and 60m charts and see how RSI(5) went overbought and stayed overbought a few bars after we entered and stayed overbought through the entire session. This is good. The more overbought bars the merrier b/c I am getting higher highs and higher lows! This combined with [5] told me to leave my initial stop in place and not tighten nor exit the market. If I did not get either this confirming indicator or [5] I would start moving my stops tighter after the first couple bars. You could use other methods such as a parabolic stop but that will often take you out of bullish consolidations when long and bearish consolidations when short. I just use very specific if-then rules for how to tighten/widen my stops.
That's basically it. On both 30m and 60m bars prices had higher highs and higher lows, hence even if I was using a tight stop, I would not have been stopped out. That's why I said "damn!" in my previous post b/c I used
discretion thinking that today would be a low-volume day and prices would likely stay in a trading range, and that breakout on the opening bar was probably a false breakout as sometimes happens on the open. What did I do? I did not follow my system. I used what I thought was a better decision and missed a 14.00 point move! That's $3,500 on one S&P contract or $700 on an emini.
Some notes: I hate using curve-fitted parameters for obvious reasons. That is why my primary components are basic ones like S/R, breakouts, trading range definitions, etc. When I do use parameters like an MA or RSI or momentum, I use them only as confirming indicators for either pre-market or post-market decision making. If you substitute a 35- or 45-bar MA; or if you used an RSI(4), RSI(6), or RSI(7) instead of RSI(5), you would still get the same confirmations. This tells me that the system is robust and did not go through optimization.
Having said that, I do see value in optimizing. It helps me to understand the inner workings of my system and sometimes reveals hidden subtleties of the market. Sometimes you optimize and find a parameter that gives
terrible results. This is good! You now start analyzing the opposite signal and seeing if you can find a way to use whatever market behavior or tendency you may have discovered in a non-optimized way.
I hope this was helpful. I tried to provide very specific details as possible without giving too much away. I utilize different components to deal with different types of setups, this was just one specific setup for today's trade.
I also hope this lets the discretional traders reading this understand that systems trading isn't just about some magical convergence of indicators, but a sincere & scientific analysis of market behavior. You'll never find the holly grail, but all you need is to find situations where your probability of success is greater than your probability of failure. For example, almost everyone looking at SP01Z can tell me where the most recent support is by looking at lowest low on 11/21, 11/16, and opening gap on 11/13. But with scientific analysis you can look at how price behaves around support. How many times was the low within ATR(X) range of support? At what intervals did this occur? How many times did RSI go overbought down into support. How many times was RSI oversold breaking through resistance? Do these things say anything about how likely support will hold? Do they say anything about probability of X% move if support does not hold?
This is what systems traders do. Just remember to avoid the fools goal of systems building and make sure that you test for robustness (i.e. not optimized) and scientific significance (not coincidence). Many systems available for purchase out there is fools gold. They are overfly curve fitted (optimized) or only worked for a certain time period (concidence).
Good luck mining.