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In this part we will explore the second indicator that I use which helps us in understanding the dynamics which happens as price action unfolds, i.e. points where price turns, also known as "Imbalances". Adam Grimes in his book "The Art and Science of Technical Analysis" says something interesting about Imbalances.

Imbalances happen in the Limit Order book (LOB), however in the absence of LOB info. we can use executed order info. as a proxy to access LOB imbalances. The indicator known as “Volume Delta” tries to do just that. It looks at volumes executed at ask vs. volumes executed at bid to make an assessment of an imbalance.

Delta here is defined as - The net difference between the buying and selling (volume) at each price (footprint delta), each bar (bar delta), or the entire day (cumulative delta).

All that you need to know about delta is here - https://marketdelta.com/what-is-delta/ and it makes no sense to reinvent the wheel, what I think is of more value to the readers here is to know how to use it in the context of NIFTY.

Delta becomes important only at points where there is a divergence, meaning price moving in one direction but delta getting skewed in the opposite direction or in other words – More aggressive buying as the price goes down and more aggressive selling as the price moves up  Such divergences point to a possible change in trend or a reversal.

Now it’s important to understand that this indicator measures divergence caused by aggressive buying or selling i.e. through Market Orders, but in reality passive limit orders could also cause both reversals and continuations and in NIFTY the ratio of market orders to limit orders would be close to 30:70, so one has to factor that in.

At this point I want to categorically say that as far as I know there is no programmatic way of determining if an execution is a market, limit, or a stop order. So the idea that attributes “aggressiveness” to market order driven (long/short) at that price point is not correct, it could always be stop’s being hit as well, or for all you know it can also be marketable limit order. This is the reason why divergences per-se can be both a point of reversal or continuation.

Let’s look at the following chart.

In the image above – The Red colored candles mean (Greater than “x” size volume at Ask compared to Bid) and the Green candles mean (Greater than “x” size volume at Bid compared to Ask) in that specific bar. X can be set to a User defined value or you could ignore it totally and let the indicator point you to every imbalance that occurs. This is an illustration of "Per Bar Delta" which is what I use.

As you can notice there are some divergence signals which act as points of continuation and some act as point of reversal, meaning some Red markers which don’t lead to a fall instead cause further up-move and some green candles which don’t lead to a raise but instead cause a further fall.

I repeat this, because a lot of novices buy into the fact that this (Indicator ie not the idea of Imbalance) is some sort of a holy grail and all that they need to do is follow the divergence signals and buy or sell accordingly, twitter traders and indicator sellers don’t make life any easy either.

That’s the reason we really need to use this indicator within the probabilistic context of the market structure of a given product.

There is another nuance in terms of the input factor for this indicator usually Volume Delta Indicators come with two modes of inputs – Up/Down Tick and Bid/Ask, choosing either of these can also alter the output.

At the end, like all other indicators this is no holy grail stuff, however can be an extremely useful reference if you can combine it with market statistics and other indicators referenced in this series.