Postflop Calculations

Postflop Calculations in HRC

HRC Pro's postflop calculation feature allows for detailed analysis of specific scenarios beyond preflop. The postflop solver is seamlessly integrated with the existing preflop tools and will feel familiar to existing users. This document provides comprehensive information about how to effectively use these features. It covers dedicated postflop analysis, abstraction options, and other functionalities to help you analyze and refine your postflop strategies.

What to Expect

• Seamless Integration: Effortlessly create and analyze postflop scenarios directly within the HRC interface, building upon existing preflop calculations.
• Versatility: Support a wide range of scenarios, including heads-up and multiway pots, various equity models like MTT ICM and PKOs.
• Accuracy: Automatically incorporate all relevant bunching effects from the preflop simulation into the postflop analysis.

Limitations

• Competing with Specialized HU Solvers: The postflop solver is not designed to compete with specialized solvers that focus exclusively on heads-up scenarios and don't consider bunching effects. In simple heads-up spots, such specialized solvers will offer better performance compared to HRC's Monte Carlo methods.
• Combo Locking: Combo locking is not currently supported for postflop calculations. However, frequency locking is already available.
• Report Generation: Comprehensive report generation for postflop solutions is not yet available. As a workaround, you can use the hand history generation feature to export relevant data and generate reports in external trackers.

Setting Up Postflop Calculations

To begin, you'll need a standard Monte Carlo preflop calculation. Next, select a specific postflop line from your preflop analysis and click Hand: Create Postflop Calculation. This will allow you to choose a specific board and configure the betting options for the rest of the hand, initiating an individual calculation for that scenario. The calculation will begin at the start of the street for the selected node.

This new calculation inherits the following from the original setup:

• Equity model
• Entry hand ranges (including folded ranges for bunching)

Once set up, this calculation becomes independent. Any future changes to your preflop hand ranges will not affect it.

Postflop Abstraction Options

Dedicated postflop calculations focus on specific board runouts, allowing for more accurate hand bucketing compared to preflop calculations that must consider all possible runouts. HRC offers several abstraction options for postflop calculations, each providing a different balance between accuracy and calculation speed:

[HQ+] Strict

Maintains full accuracy, only leveraging suit isomorphisms for simplification.

[HQ] Balanced

Ignores some minor suit information that is rarely relevant for human decision-making, resulting in minimal impact on accuracy.

Details by Street

• Flop: Ignores single blockers to backdoor flush draws (BDFDs).
  For example, Ts 5c 3d with KdQs, KsQh, and KdQc are all considered the same.
• Turn: Merges missed flop BDFD blocker suits, treating hands equivalently if they block the same number of BDFDs.
  For example, on a board of As 9c 7h, 3c:
  • 5s6h == 5s6s (Each blocks one 5 and one 6 of a BDFD suit)
  • 5h6s != 5h6d (Diamonds weren't on the flop, so they are treated differently)
  • Any club cards are explicitly tracked because there is a club flush draw.
• River: Discounts blockers to flop BDFs that did not materialize on the turn.
  For example, on a board of As 9c 7h, 3c, 2d, ignore all spade, heart, and diamond suit information; only track club cards.

[MQ] Relaxed

Takes the suit simplifications further, but still provides reasonable accuracy. It is a good option for later streets in high-accuracy simulations.

Details by Street

• Flop: Like Balanced, but also does not differentiate between the suits of BDFDs, tracking only the presence of a BDFD, not the specific suit.
  For example, on a board of Ts 5c 3d, the combos of KdQd, KsQs, and KcQc are all treated identically.
• Turn: Ignores any BDFD information that did not materialize on the turn, tracking only the card suits that contribute to or block flush draws.
  For example, on a board of As 9c 7h, 3c, ignore all spade, heart, and diamond suit information; only track club cards.
• River: Similar to Balanced, but additionally discounts any one-card flush draw blockers and merges all river suits that did not complete flushes.
  For example, As 9c 7h, 3c, 2d == As 9c 7h, 3c, 2h (rivers that didn't complete flushes are treated identically).

[LQ] IR, Imperfect Recall

This option is based on the 16k bucket option offered for preflop simulations but is filtered to include only the relevant runouts. It provides drastically smaller calculations but makes major compromises regarding accuracy, especially for river strategies. Additionally, when using this option, EVs will not be displayed for that street.

Abstraction Recommendations

For the first street of your calculation, Strict or Balanced is generally the most appropriate choice, as these options provide the highest accuracy. To save both memory and calculation time, consider using Balanced or Relaxed for later streets. You can resort to the low-quality [LQ] bucketing for later streets if calculation time is a priority or if the setup is otherwise too large.

Some scenarios, such as multiway flop calculations, can result in very large game trees with the high-quality options. In these cases, it may be necessary to calculate the flop using [LQ] bucketing for the river. This means that while the flop strategy will be reasonably accurate, the river strategy will be of lower quality. If you need precise river strategies later, you can quickly re-calculate a higher quality version by setting up a dedicated river simulation for a specific line and board with high quality bucketing.

Displaying Combo Information

You can access detailed information about the EV and strategy of each hand combo through the hand grid, similar to how it works for preflop calculations. However, there's a key difference: when you hover your mouse over a hand class, a smaller grid pops up displaying information about each combo within that class. You can find further details in the tooltips for that smaller grid.

Additionally, a new suit selection dropdown at the top of the hand grid allows you to filter the display by the suits of the hole cards.

Navigating Board Runouts

When you run a postflop calculation in HRC, it automatically generates results for all possible board runouts for subsequent streets. To view information about a specific runout, use the board selector button below the strategy tab. You can access strategy details for a node via the hand grid, but only if the board has been specified for that street.

It's important to note that you don't need to re-calculate when switching between runouts within a calculation. This feature is simply a filter for display purposes and doesn't affect the underlying calculation.

Postflop Strategies within Preflop Calculations

You can explore postflop strategies directly from your existing preflop calculations using the board selector at the bottom of the hand tab. This gives you immediate access to all possible boards. However, keep in mind that the displayed strategies may not be entirely accurate, because preflop calculations use a higher level of abstraction and don't store detailed postflop strategy information by default.

This option is intended only for exploratory browsing and getting a quick first impression of postflop strategies. Due to the limitations in accuracy, dedicated postflop calculations should be used when you need precise results.

A warning message will appear when viewing a node without averaged strategy data. To improve accuracy, you can add this data using the Hand: Add Postflop Strategy Data option. Be aware that this will approximately double the size of the calculation and require new sampling. Even with this added data, the results will still not be as precise as those obtained from a dedicated postflop analysis.