Hi all, In the Facebook group Backgammon News, Wayne Joseph raised some questions about the values displayed in the Temperature map. I've posted extracts from the discussion below for context, but the gist of it is.
The user was confused by the equities in the Temperature map being normalised to a 1-cube for both cube actions. This obscures the effect of doubling the stakes. 1. I think the values in the doubled part of the map should be normalised to a 2-cube rather than a 1 cube. This would make the value in the Top left to f the Doubled Box (Item 2) on the screen shot equal to the Double, Take Equity in the Analysis window. It would also make it easier to compare the value of each roll, with and without a double. 2. The scale bar display does seem to anticipate that the right-hand side will show the doubled equity. In the example below, the max scale of +1.385 is about twice the value of the best roll 66 +0.659 for 66 and the minimum scale -0.077 is about twice the value of the worst roll -0.036. I also think the map could benefit from showing market losers in a different colour. I don't find the shades of red all that easy to follow. https://www.facebook.com/groups/1017340842031433/posts/1897126800719495/?comment_id=1899875730444602¬if_id=1707695820400391¬if_t=feedback_reaction_generic&ref=notif Transcript follows: Wayne Joseph Sho Sengoku's Temperature Map is very useful to visualize the dangers and jokers of a move, as well as the volatility of cube decisions. Can anyone give clear definitions for what the items labelled 1-4 represent? I couldn't find a full explanation in the manual. [Ian notes - my previous attempt to post his screenshot of the temperature map failed]. HdvGAAiw3w0YAA:UQmgAAAAAAAE GNU Backgammon Position ID: HdvGAAiw3w0YAA Match ID : UQmgAAAAAAAE +24-23-22-21-20-19------18-17-16-15-14-13-+ O: gnubg | O O O O | | O O X O | 0 points | O O O | | O O X O | | O | | | | | | | | | | | | |BAR| |v 5 points match | 6 | | | | X | | | | X | | X | | X X | | X X | On roll | O X X | | X X | 0 points +-1--2--3--4--5--6-------7--8--9-10-11-12-+ X: ianshaw (Cube: 2) Pip counts: O 103, X 113 Cube analysis 4-ply cubeless equity +0.273 (Money: +0.270) 0.618 0.092 0.003 - 0.382 0.060 0.001 Cubeful equities: 1. No double +0.513 2. Double, pass +1.000 (+0.487) 3. Double, take +0.384 (-0.129) Proper cube action: No redouble, take (20.9%) Ian Shaw 1 & 2 are the overall equities of each option (the sum of the 36 rolls). 3 & 4 should be the max and min range of the colour scale. But the outliers on the map in your picture are -0.036 to +0.659, so I'm not sure. Wayne Joseph For items 1+2, please could anyone explain in layman's terms why cubing to 4 (ownership) results in around a noteworthy 60% decrease in the overall normalised equity (equivalent money game), given they are based on *exactly* the same 36 rolls? 60% less equity sounds like a lot to give up 'just' for redoubling. Ian Shaw If you look at the top-left corner of the 4-cube map, the value (+0.221 )is about half the value of the Double/Take Cube Analysis (+0.424). That's because the values are in emg, so they have been re-normalized. This allows you to compare the value of the individual rolls on an equal basis, to see how much better they are. For instance, the equity for 66 is +0.648 on a 4-cube, but on a 2-cube it is +0.965. This will be because after 15/3*(2) you can probably cash most sequences if you own the cube, but having redoubled you must still complete the bearoff to win. Wayne Joseph It's highlighted to me I still don't have my head around 'equity' (which internally, cognitively I kind of interpret as 'overall reward-overall risk'). Or the utility of those numbers. >> +0.648 on a 4-cube, >> but on a 2-cube it is +0.965. Attached is a screenshot of the position after rolling 66 and hitting. Looking at the screenshot, those numbers feel very counterintuitive (probably just me) To me, OTB, at 83% favourite I would much prefer to be on a 4 cube (opponent held) in the screenshot, rather than holding a 2 cube. It feels like I would be fairly confident of bringing this home, for more reward (equity?) i.e. 4 points is better than 2 ...but then I would have substantially *less* 'equity'. In a situation that feels 'better'??? >> +0.648 on a 4-cube, >> but on a 2-cube it is +0.965. May I sense check - OTB at 83% favourite would you (or others) prefer to be in the post 66 position on a 4 cube (opponent held). Or would you really prefer to be just holding the cube at 2? Ian Shaw 66 was your best roll. So yes, you wish you had doubled if you roll it. Your doubled equity of 0.648*2 is better than the 0.965 from not doubling. If you still hold the cube, you are going to double him out unless he rolls 45 or 46, which is why the equity is almost 1.0. On the other hand, if you roll that 62, you'll be very glad not to have doubled the stakes. Wayne Joseph Ok, from what you said, it sounds like there is a extra cognitive step required of manually multiplying all values in the 4 cube section by 2 to more easily compare like for like? It feels like it might be a clearer and more intuitive UX to have the 4 cube values presented with the necessary subsequent multiplication step performed already? (i.e. 1.296 vs 0.965 after 66 is much more intuitive to me in showing 66 has more value (and the difference of that increase) after cubing, rather than displaying 0.648 vs 0.965 which 'sounds' worse) Ian Shaw I think you have a good point. The numbers in the Double window should reflect the values in the analysis display, but in more detail. If I remember, I'll post some of this discussion on the gnubg mailing list. Perhaps one of the devs has a counter argument. -----Original Message----- From: bug-gnubg-bounces+ian.shaw=riverauto.co...@gnu.org <bug-gnubg-bounces+ian.shaw=riverauto.co...@gnu.org> On Behalf Of Philippe Michel Sent: Tuesday, February 20, 2024 9:53 PM To: bug-gnubg@gnu.org Subject: Preview of forthcoming gnubg release I have uploaded a new gnubg Windows build at http://philippe.michel7.free.fr/gnubg/ This should fix the bugs in 1.08.001 reported here or by other means: - the gnubgautorc file corruption - the "Move" quirk in the GUI menus - "Analyse/Show Records" becoming inactive after using "Analyse/Show Records/Plot History" (reported and fixed by Isaac Keslassy) - a mistake in the description of the Isight racing count and improve the pasting of XGIDs by accepting those copied from XG by a Ctrl+C (copy XGID+Board) instead of only those from Ctrl+Shift+C (contributed by Takahashi Kaoru). Plus complete Finnish and Japanese translations. Regarding the gnubgautorc file corruption, I couldn't reproduce it at will and it happened only once for me in a week of use of the unfixed version. I'm confident it should be ok now but, if the problem hit you more frequently, please test this new version and report how it goes. Barring another bad surprise on the gnubgautorc issue I will build and upload a 1.08.002 version this week-end.