In 2008 we introduced a concept that we labeled TPS, which stands for:
Originally presented as a stand-alone strategy, the core ideas behind TPS have turned into a methodology that can be applied to a variety of different mean reversion strategies. Since the overall concept has held up incredibly well over the intervening years, it’s worth a quick review.
With TPS, we’re trying to get all three components – time, price, and scale-in – working in our favor. At a high level, here’s how it works for a long mean-reversion strategy:
- When a pullback occurs and the strategy signals an entry, buy a small initial position.
- If the stock or ETF becomes more oversold (more on this in a minute), then increase your position size by scaling in, i.e. purchasing more shares.
- Step 2 may be repeated multiple times if the price continues to pull back and the scale-in rules allow it.
Typically the criterion for scaling is simply a closing price that’s lower than the previous entry price. However, other rules may be used to determine when a stock has become more oversold. For example, we might enter a trade when ConnorsRSI is less than 20, and then scale in if ConnorsRSI drops lower. If the first scale-in occurs when ConnorsRSI is 17.8, then we would scale in a second time if ConnorsRSI closed lower than 17.8 at any time before we exited the trade.
Different strategies utilize different scale-in ratios. Common ratios include 1-1, 2-3-5, 1-2-3-4 and 1-2-3-4-5. The ratio is created by using each digit as the numerator, and the total of the digits as the denominator. For example, with 2-3-5 scaling, we can have an initial entry plus two additional scale-ins. The initial entry would be 2/10 (20%) of a full position, the first scale-in would be an additional 3/10 (30%) of a full position, and the second/final scale-in would be 5/10 (50%) of a full position.
The biggest advantage to this approach is that by scaling in at lower and lower prices, we are lowering our average entry price. This, in turn, increases our chances of a profitable exit.
A less obvious benefit of TPS is that it can allow us to enter trades using less stringent entry criteria. In many cases, this will increase both the number of trade signals generated and the average gain per trade.
Consider a very simple strategy with the following rules:
- Buy a stock that has an RSI(2) value below X, where X = 10, 20, or 30.
- Sell the stock when it closes above the 5-day moving average, MA(5)
Here are the results when the strategy is applied to a universe of liquid stocks and TPS is not used:
Here are the results when the strategy is applied to a universe of liquid stocks and TPS is not used:
| Var # |
# Trades |
Avg % P/L |
% Winners |
RSI(2) Threshold |
Scaling |
| 1 |
58463 |
0.42 |
66.80 |
10 |
1/0 |
| 2 |
81917 |
0.34 |
66.33 |
15 |
1/0 |
| 3 |
102258 |
0.29 |
66.21 |
20 |
1/0 |
As we would expect, as the entry criteria becomes more stringent (lower RSI(2) threshold), we generate fewer trade signals but a higher average gain per trade.
Now let’s see what happens when we use 2/3/5 or 1/2/3/4 scaling. In all cases, we scale in further when the price closes below the previous entry price.
| Var # |
# Trades |
Avg % P/L |
% Winners |
RSI(2) Threshold |
Scaling |
| 4 |
58463 |
1.38 |
80.02 |
10 |
2/3/5 |
| 5 |
81917 |
1.30 |
79.65 |
15 |
2/3/5 |
| 6 |
102258 |
1.24 |
79.61 |
20 |
2/3/5 |
| 7 |
58434 |
1.62 |
83.46 |
10 |
1/2/3/4 |
| 8 |
81917 |
1.54 |
83.21 |
15 |
1/2/3/4 |
| 9 |
102005 |
1.49 |
83.21 |
20 |
1/2/3/4 |
Notice that if we keep the RSI(2) threshold the same, then the number of trades remains stable, but the average gain per trade rises by a factor of 3 to 5. Alternatively, we can use a higher RSI(2) threshold to increase both the number of trades and the Average % P/L. For example, consider Variation 1, which uses no scaling and an RSI(2) threshold of 10. In back testing, this strategy variation generated 58,463 entry signals, and an average gain per trade of 0.42%. Variation 5 uses an RSI(2) threshold of 15 and 2/3/5 scaling, and generated 81,917 trade signals and an average gain of 1.30%. Using 1/2/3/4 scaling (Variation 8) increased the gain per trade to 1.54%.
As you can see, TPS is a powerful tool that can potentially increase the returns of many existing trading strategies. TPS is just one of many topics that will be covered in detail during the upcoming 2013 Swing Trading College.