Time and Sales vs Order Flow Cumulative Delta

[rezamerik]

My understanding is that Order Flow Cumulative Delta is basically a chart for Time and Sales (correct me if I'm wrong though). With that, a few questions:

1 - Are the number of buys and sells used to calculate the cumulative delta based on both market orders and limit orders? Like any buy above/below ask/bid is considered a buy, and any sell above/below bid/ask is considered a sell? Or is the delta calculated only based on the market orders?
2 - Time and Sales start printing after you connect to the data feed, and my understanding is that there is no way to have access to the transactions that occurred before you were connected to the data feed. Is this the same for the cumulative delta plot, and you will only see data for it after you connect to a data feed? Is there a way to see prior transactions that occurred prior to your connection, both in time and sales and on the cumulative delta chart?
3 - How is it possible that sometimes the tape is green and most orders are buying orders (sometimes with large buy orders), but the price keeps going lower and lower? Does this imply that bears are covering their short positions, and thus more buying does not necessarily mean the price will go higher in this case?

Appreciate your thoughts on these questions

[NinjaTrader_Jason]

Hello rezamerik,

1. The Order Flow Cumulative Delta indicator accumulates the volume of any order filled.

2. You could use the Playback connection to replay historical data in realtime in the T & S window. Please see the link below for information on the Playback connection.

https://ninjatrader.com/support/helpGuides/nt8/NT%20HelpGuide%20English.html?playback_connection.htm

If the 'Delta type' setting is set to 'Bid Ask' for the Order Flow Cumulative Delta, you need historical bid ask stamped tick data to have it plot on historical data. You can view the link below to check what providers offer such data.

https://ninjatrader.com/support/helpGuides/nt8/NT%20HelpGuide%20English.html?data_by_provider.htm

3. If the market is bearish, but the Order Flow Cumulative Delta is bullish, it can indicate the market will become bullish. You can find an example the other way around at the link below under 'Using the Order Flow Cumulative Delta'

https://ninjatrader.com/support/helpGuides/nt8/index.html?order_flow_cumulative_delta.htm#OrderFlowCumulativeDeltaOverview