Volume EPO – One bar, seven volume stories Volume EPO – One bar, seven volume stories (VAKFN, Borsa Istanbul)
This idea illustrates how different volume-classification methods can produce very different interpretations of the same bar. The Volume EPO overlay is used as a research tool to display seven methods side by side in a compact HUD.
The example is taken from VAKFN on Borsa Istanbul. On this market, TradingView provides extended intrabar volume data (BIST volume data plan), which allows the Intrabar row of the table to be built from lower-timeframe up/down volume and used as a high-precision benchmark.
Price is shown on the daily chart inside an ascending channel. The last daily bar in that structure is analyzed with the Volume EPO table on the right. Total volume on that bar is the same for every row (66.49M), but each method splits it into buy / sell / delta differently:
- Intrabar (Ref) – lower-timeframe up/down volume
≈ 36.66M buy vs 29.83M sell → delta +6.83M (moderate net buying; benchmark “truth layer”).
- BVC (Smart) – probabilistic split via normal CDF on normalized price change
Delta ≈ +7.61M, very close to Intrabar (Diff ≈ 1.1%), confirming a mild buy imbalance.
- Tick Rule – classic uptick/downtick classifier
Because the close is above the previous close, the whole 66.49M is classified as buy volume
→ delta +66.49M (Diff ≈ 90%), an extremely bullish reading.
- Lee-Ready Style – delayed midpoint quote test with Tick fallback
On this bar the close falls on the sell side of the delayed midpoint, so the entire volume is classified as selling
→ delta −66.49M (Diff ≈ 110%), the exact opposite of Tick Rule.
- Wick Imbalance – geometric supply/demand from upper vs lower wicks
A strong upper wick and weak close again lead to a full sell reading
→ delta −66.49M (Diff ≈ 110%).
- ML-Logit – logistic model of normalized return and volume deviation
Shows only a small negative imbalance
→ delta ≈ −1.38M (Diff ≈ 12.1%), close to neutral flow.
- Geometry – legacy CLV-style candle approximation
With the close near the low of the range, more volume is assigned to sellers
→ delta ≈ −33.25M (Diff ≈ 60.1%), strong selling.
On this single daily bar of VAKFN, the conclusions range from “mild net buying” (Intrabar, BVC) to “massive buying” (Tick Rule), “massive selling” (Lee-Ready Style, Wick Imbalance), “almost neutral” (ML-Logit), and “strong selling” (Geometry).
Only the Intrabar row uses actual lower-timeframe up/down volume from TradingView; all other rows are models built on top of OHLCV. Access to deeper intrabar history on small timeframes (such as 1s/5s, depending on data plan and subscription level for BIST) strengthens this benchmark layer and makes it easier to see which methods stay close to the underlying flow and which ones drift away.
This idea is presented as a research and educational example on VAKFN, not as a trade signal or financial advice.
