SMI Trading Strategy: Calculation, Settings, and a Testable Rule
The Stochastic Momentum Index (SMI) compares a smoothed distance from the recent range midpoint with a smoothed range. Its centered scale helps describe that relationship. It does not supply an expected win rate or prove that it outperforms RSI or the standard stochastic oscillator.
Calculate the SMI before interpreting it
Pineify finds the highest high and lowest low over K Length. It subtracts their midpoint from the close, then applies two successive EMAs to that relative distance and separately to the high-minus-low range. SMI is 200 times the ratio of those smoothed series. A separate EMA of SMI produces the signal line.
The current inputs are:
| Input | Default | Role |
|---|---|---|
| K Length | 10 | Window for the high/low range |
| D Length | 3 | Length for each of the two EMA smoothing passes |
| EMA Length | 3 | Signal smoothing applied to SMI |
These are three distinct controls; the third is not a second range-lookback defaulting to 5. The TradingView SMI documentation describes the same calculation structure.
Because the numerator is smoothed, a positive value describes the smoothed relative distance. It need not mean the current close alone is above today's rolling midpoint. A zero or unavailable range denominator also needs attention before a strategy treats the result as a signal.
Define thresholds as part of the rule
SMI is usually displayed on a -100 to +100 scale. Reference levels such as +40 and -40, or a custom +50 and -50, are configurable choices. Changing the scale from the standard stochastic does not itself provide an earlier or more accurate warning.
A cross above the signal line means SMI has crossed its EMA. A positive SMI value and a bullish crossover are different observations. Neither guarantees that price will rise next. Strong trends can coexist with extended readings near one end of the scale.
Specify one baseline strategy
An illustrative research baseline might enter long after a confirmed SMI cross above its signal and exit on a confirmed cross below. Decide whether a threshold filter is required before the crossover, whether positions can reverse, and what happens when a new signal arrives while already in a trade.
Record the symbol, timeframe, session, dates, all three lengths, order timing, costs, and sizing. Add any independent stop or target with a precise rule. TradingView's strategy documentation explains why a historical signal bar and its simulated fill may differ.
A trend filter or volume filter is a separate hypothesis. Compare it with the unchanged baseline and report both trade count and exposure. More conditions can exclude winning trades as well as losing trades; they do not automatically make signals stronger.
Handle divergence and evaluation timing
A bullish divergence compares a lower price low with a higher oscillator low. The bearish counterpart compares a higher price high with a lower oscillator high. Specify how pivots are paired and when they become confirmed. Do not backdate an order to a pivot that required later bars to identify.
Keep development and evaluation periods separate. Retain the full list of settings tried and inspect results across nearby settings. For a stock-universe test, specify point-in-time membership, delisted securities, corporate actions, and portfolio construction rather than assuming a current constituent list is an unbiased historical sample.
Report evidence that supports the claim
A reproducible result needs executable rules, source data, dates, costs, and full trades or portfolio equity. This article reports no verified 67% CAGR, 43% win rate, or 48% drawdown. A percentage table without those materials cannot establish expected future results.
Win rate must be assessed together with average gain, average loss, costs, and tail losses. A target reward-to-risk ratio is not a realized payoff ratio. Position sizing controls planned exposure but cannot eliminate gaps or guarantee a maximum account drawdown.
Pineify's Visual Editor can configure SMI conditions and generate a script for review. Record the actual signals, trade rationale, and outcomes in a journal. Automatic inference of your reasoning or a demonstrated edge after a fixed number of trades is not promised.
What win rate should I expect from an SMI strategy?
No universal rate follows from the indicator. It depends on the complete rule, data, costs, and evaluation procedure.
What are Pineify's SMI defaults?
K Length 10, D Length 3, and EMA Length 3. They describe the current configuration, not optimized trading settings.
Is SMI the same as SMI Ergodic Oscillator?
No. This SMI uses distance from a high/low midpoint. Pineify's SMI Ergodic Oscillator uses TSI minus its EMA signal.
