Know Sure Thing

The Know Sure Thing is Martin Pring's weighted momentum oscillator: four rate-of-change readings, each smoothed by its own simple moving average, summed with weights of 1 through 4 and plotted with a signal line for crossover reference. Defaults are the classic ROC lengths of 10/15/20/30 smoothed by 10/10/10/15-period SMAs, with a 9-period SMA signal line. The KST and Signal lines plot around a dashed zero level — the standard raw implementation of Pring's design.

How to Trade the Know Sure Thing?

• KST crossing above the Signal line: weighted momentum turning up against its own recent path — the primary bullish trigger.
• KST crossing below the Signal line: the opposite turn, often used to lighten exposure.
• KST above or below zero: the regime read; above zero the weighted sum of the four smoothed ROCs is positive.
• Divergence with price: a KST that fails to confirm a fresh price extreme flags fading momentum behind the move.

Know Sure Thing Settings

• ROC Length #1 (default 10): lookback of the shortest rate of change — the component that bends the line earliest.
• ROC Length #2 (default 15): second rate of change, weighted 2x in the sum.
• ROC Length #3 (default 20): third rate of change, weighted 3x.
• ROC Length #4 (default 30): the longest ROC; carrying weight 4, it shapes the oscillator most.
• SMA Length #1 (default 10): smoothing applied to the first ROC (RCMA #1).
• SMA Length #2 (default 10): smoothing of the second ROC.
• SMA Length #3 (default 10): smoothing of the third ROC.
• SMA Length #4 (default 15): smoothing of the fourth ROC.
• Signal Length (default 9): simple moving average of the KST that forms the Signal line.

Alerts

Bullish Cross and Bearish Cross fire on signal-line crossings, while Bullish Zero Cross and Bearish Zero Cross fire when the KST crosses zero.

Frequently Asked Questions

How does the Know Sure Thing differ from MACD?

MACD measures one spread — a fast EMA minus a slow EMA — while KST sums four smoothed rate-of-change horizons with rising weights. Both are read through signal crosses, the zero line, and divergence, but KST turns more deliberately and whipsaws less in exchange for later triggers.

What timeframes suit the default settings?

The 10/15/20/30 set with 10/10/10/15 smoothing is the widely published daily-chart configuration, though the lengths are counted in bars and apply to any interval. Shortening the ROC lengths speeds the line up at the cost of noise.

Can I trade KST crossovers on their own?

Better treated as momentum context than a complete system: every component is a lagged, smoothed rate of change, so crossovers confirm turns already underway. Pair them with price structure or a trend filter.