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scott
07-23-2024, 06:07 PM
I had a little bit of downtime, and as often happens when I have such downtime, I decided to use it on satisfying some statistical curiosities, specifically the value of multiple pick swaps in the same draft.

Right off the bat, some acknowledgements and a call for others to expand on this work.

Shout out to Ariel (https://www.spurstalk.com/forums/member.php?u=3526), who does some fantastic statistics and quant work on this message board for nothing more than the gratitude of other Spurs fans. Often times, Ariel's high quality quant work makes me lazy, and just rely on them (sorry Ariel, I don't actually know whether you are a he or a her, or anything else) to actually calculate things. However, Ariel does inspire me to actually dig in from time to time and do my own work, which is a good thing. Thank you for being a great contributor to my free time when I'm thinking about the Spurs.
Also a shout out to Seventyniner (https://www.spurstalk.com/forums/member.php?u=17327), who provided a fantastic link which validates one of the key assumptions behind this analysis, which I'll go into a little later.
Lastly, thanks to a few of my favorite posters who contribute really high quality, quantitative based opinions that I really cherish. I wanted to specifically shout out SpursBills (https://www.spurstalk.com/forums/member.php?u=18470), Chinook (https://www.spurstalk.com/forums/member.php?u=37557) and LeBowen (https://www.spurstalk.com/forums/member.php?u=54457). There are many more people who's opinions I really enjoy and value on this board, but they seem to put a lot of thought, logic and supporting data behind their takes which pushes me to not be so lazy with my own.


With that said, let's get into it.

The basic question presented here is, what is the value of adding multiple swaps in a given year? Swaps on their own, I really don't place a lot of equity in - they tend to be worth about as much as an early second round pick in terms of trade value (Credit, Zach Kram: https://www.theringer.com/nba/2022/10/12/23399637/nba-draft-swap-picks#:~:text=The%20results%20suggest%20that%20pic k,swap%20returns%20second%2Dround%20value!). However, where Swaps really add value, is when viewed holistically with your own pick (which is gets attached to) and the potential outcomes for that single pick, now enhanced with the potential results of a different team's season.

I wanted to take a look at the degree to which a team's pick is enhanced by adding multiple swaps in a given year, which I will refer to as "vertical swaps". With the Spurs having DAL and MIN swaps (ignoring the Top-1 protection for now), I was curious at just what that meant for the potential outcomes for that pick. So this led me to a more specific question: What are the odds that a pick will land in X range for an n number of swaps obtained.

To do this, there are some variables which are either very difficult to model or I just haven't wrapped my brain around how to do it yet. For example:

Protections on swaps add some difficulty. I know this can be solved, but I just haven't taken the time to do the work in building out the algorithm for it, and frankly I doubt I will.
The probability that a team will be good at any given point in the future, and the fact that some franchises are historically better than others. I deal with this another way, which I'll explain below.
The draft lottery. This adds a wrinkle that I don't really want to deal with right now, so I'm just ignoring it completely and (admittedly incorrectly) assuming that swaps occur before the lottery. This is not correct, and this is acknowledged from the get go, but it saves me the trouble of laying on an extra set of probabilities that I haven't thought about how to work with yet. I'm hoping maybe someone else wants to pick up the torch on this front.


On order to deal with the second bullet point, I'm going to look at far-out swaps. I had an existing hypothesis that after 5 years, the outcomes in the NBA were all subject to natural variance, and that seems to be supported by an article that Seventyniner (https://www.spurstalk.com/forums/member.php?u=17327) directed me to (here: https://www.theringer.com/nba/2019/6/27/18760309/nba-title-windows). Long story short, that 5 years into the future, only about a third of good teams are still good; a quarter of bad teams are still bad; and half of decent teams are still decent. To me, this is good enough to support the hypothesis that you can't really predict which teams will be good or bad in 5+ years.

So with that, I'm going to assume that at 5+ years out, all swaps have an equal probability of landing anywhere between pre-lottery seeding of 1 (worst team in the league) to 30 (NBA champs).

One last key note when thinking about swaps: whether or not the swap conveys, at some point becomes irrelevant. What matters is whether or not the ultimate outcome falls within a certain range, and that outcome may actually come from your own pick, not a swap. This is because I approach the valuation of draft picks from a trade value perspective, and how much more valuable do swaps make your pick. The acquiring team cares not whether or not the swap conveys, they merely care about the ultimate outcome (and so should you, if you don't trade the pick). So with that said, we are looking to see what the probability is that our pick falls within a certain range.

I used the concept of complementary probability. Instead of finding the probability that at least one of my picks end up in a range, I found the probability that none of my picks were in that range and then subtracted that from 1. The result is the following table:

https://i.ibb.co/QnMs8YM/Vertical-Swap-Odds.png

The way to read this table is as follows: the vertical axis is the number of swaps you own plus 1 (your own pick), and the horizontal axis is the desired range you want your pick to land on. Let's start with some very basic examples to help understand what is happening here. If your final ranking is random (which we are assuming) and you only have your own pick with no swaps, then there is a 50% chance your pick will land in the top half (top 15). That is the upper left hand corner of the table. Should be simple. Alternatively, if you owned swaps with EVERY team in the league, you would have a 100% chance of landing the #1 spot, because there are literally no other potential outcomes.

What this table shows, however, is that you need not achieve true certainty to have virtual certainty. For example, if you're desired range is a lottery pick (Top-14 position), you only need to own 4 swaps to have a greater than 93% chance of getting a lottery pick. By the time you have 7 swaps, you have greater than a 99% chance. Where you see a 1.000 in the table that is NOT black, that is a greater than 99.9% chance (but not true 100%). Black cells mean a true 100% certainty.

As you can see, in 2030, when the Spurs have two swaps (ignoring the protections), they have a 86.2% chance of our pick ending up a lottery pick. That makes that pick extremely valuable, because otherwise a pick with no swaps would only have a 46.7% chance of being a lottery pick.

There are some other insights I'll probably add on to this over time, and I hope folks will find this interesting and comment on.

Thanks for taking the team to read this.

Chinook
07-23-2024, 07:48 PM
Awesome, thread scott. Great work that will only become more interesting as we get closer to 2030. One interesting factor to me is that swaps are both voluntary and non-simultaneous. Like the Spurs aren't getting (ignoring protections), the best of SAS30, DAL30 and MIN30. They're getting the option to pick between of i)MIN30 and ii) whichever they prefer of SAS30 and DAL30. The Spurs could decide to decline a swap for something like cap reasons. Or they could agree to extinguish one of the swaps in exchange for some trade relief. As far as I know, extinguishing a swap counts as a "touch", just as altering protections does.

What I'm less sure about is what rights the other teams have in this. Let's say the Wolves in 2030 finish with the second-overall pick (so the protections don't come into play), the Spurs finish with the ninth pick and the Mavericks finish with the 30th pick. (As a quick side note, the NBA is not like the NFL. The champs don't get the last picks. It's just been the case that the last year the first-overall seed won the title). Anyway, in this scenario, could the Spurs choose to swap their pick with Dallas, getting the 30th pick, and then swap that with Minny for their second pick, basically giving Dallas a lotto pick (theoretically in exchange for compensation) while Minny gets left holding the bag. If that isn't possible (and I'd hope it wouldn't be), would it be because the NBA actually prevents if or because Minny specifically traded the rights to swap its pick with the BEST of SAS30 and DAL30? Could the Spurs extinguish their swap with Dallas while maintaining their swap with Minny? It's clear enough that the reverse should be fine, as Minny comes later in the decision tree.

This might seem trivial, and indeed to the idea of this thread, it doesn't really matter. But theoretically, the actual value a team with 29 pick swaps could command might vary tremendously depending on the order of the swaps in the decision tree relative to the picks available at each stage. Like if the Spurs added every other team to their 2030 swap collection, but Dallas finished with the first-overall pick, then then entire swap chain is broken before it starts. But if the first-overall pick lies even one more step into the chain, chaos may ensue. It'll be interesting if we ever get to see those swaps in full action.

exstatic
07-23-2024, 08:03 PM
Awesome, thread scott. Great work that will only become more interesting as we get closer to 2030. One interesting factor to me is that swaps are both voluntary and non-simultaneous. Like the Spurs aren't getting (ignoring protections), the best of SAS30, DAL30 and MIN30. They're getting the option to pick between of i)MIN30 and ii) whichever they prefer of SAS30 and DAL30. The Spurs could decide to decline a swap for something like cap reasons. Or they could agree to extinguish one of the swaps in exchange for some trade relief. As far as I know, extinguishing a swap counts as a "touch", just as altering protections does.

What I'm less sure about is what rights the other teams have in this. Let's say the Wolves in 2030 finish with the second-overall pick (so the protections don't come into play), the Spurs finish with the ninth pick and the Mavericks finish with the 30th pick. (As a quick side note, the NBA is not like the NFL. The champs don't get the last picks. It's just been the case that the last year the first-overall seed won the title). Anyway, in this scenario, could the Spurs choose to swap their pick with Dallas, getting the 30th pick, and then swap that with Minny for their second pick, basically giving Dallas a lotto pick (theoretically in exchange for compensation) while Minny gets left holding the bag. If that isn't possible (and I'd hope it wouldn't be), would it be because the NBA actually prevents if or because Minny specifically traded the rights to swap its pick with the BEST of SAS30 and DAL30? Could the Spurs extinguish their swap with Dallas while maintaining their swap with Minny? It's clear enough that the reverse should be fine, as Minny comes later in the decision tree.

This might seem trivial, and indeed to the idea of this thread, it doesn't really matter. But theoretically, the actual value a team with 29 pick swaps could command might vary tremendously depending on the order of the swaps in the decision tree relative to the picks available at each stage. Like if the Spurs added every other team to their 2030 swap collection, but Dallas finished with the first-overall pick, then then entire swap chain is broken before it starts. But if the first-overall pick lies even one more step into the chain, chaos may ensue. It'll be interesting if we ever get to see those swaps in full action.

We have the option to do one swap. In your scenario, we grab Minnesota’s #2 pick.

scott
07-23-2024, 08:10 PM
Thanks Chinook! Thanks for the clarification on the 30th pick, I couldn't remember and it wasn't important enough for me to look it up at the moment.

I was very curious if the swaps could be executed the way you spelled out. If the Swaps need not be executed in particular order, in theory, if you held swaps from all 29 other teams - I was curious if it effectively gave you the right to set the draft order any way you pleased (or didn't, if you were compensated not to). For example. If Team A is terrible and get's the #1 overall pick - how much extra would they be willing to compensate you to put them at the #2 pick?

My guess is the league would not allow this, not because there is an actual fear of a team acquiring 29 swaps, but because of the incremental unintended value it adds to swaps, but surely it must be written somewhere. I'll look into the CBA on swaps a little later, but this is a very fascinating wrinkle!

scott
07-23-2024, 08:18 PM
We have the option to do one swap. In your scenario, we grab Minnesota’s #2 pick.

In the non-basketball world, it would all depend on how the contract is written... but since I've never worked in an NBA front office I don't know how these things are actually negotiated/done. Take the hypothetical where we are discussing acquiring a 2030 swap from Miami. I'd presume we can write this any way the two teams agree upon. Miami can give us the right to swap any pick we have... or Miami can agree to swap us with the Spurs natural pick... or Miami can agree to swap their pick with the next best of SAS/DAL/MIN? Of course... all subject to whatever rules the league has set forth.

Surely the NBA must have a written rule, right? It makes perfect sense that we would only be allowed to do one swap... but does it explicitly state that anywhere?

Seventyniner
07-23-2024, 08:54 PM
My (uninformed) guess is that the first swap you get in a given year is just vanilla, though it can have protections and any further swaps have to specify how they work in relation to any swaps that already exist. We would need to see the wording of the actual trade sent to the league office to really know, and I imagine it has to exist in detailed writing in order to be enforceable later.

exstatic
07-23-2024, 09:57 PM
In the non-basketball world, it would all depend on how the contract is written... but since I've never worked in an NBA front office I don't know how these things are actually negotiated/done. Take the hypothetical where we are discussing acquiring a 2030 swap from Miami. I'd presume we can write this any way the two teams agree upon. Miami can give us the right to swap any pick we have... or Miami can agree to swap us with the Spurs natural pick... or Miami can agree to swap their pick with the next best of SAS/DAL/MIN? Of course... all subject to whatever rules the league has set forth.

Surely the NBA must have a written rule, right? It makes perfect sense that we would only be allowed to do one swap... but does it explicitly state that anywhere?

We agreed to a swap with Dallas last summer, but they never agreed to swap with Minnesota, which is kind of what you’re spitballing. My thinking is that we have two swaps, but can only execute one.

scott
07-23-2024, 10:04 PM
We agreed to a swap with Dallas last summer, but they never agreed to swap with Minnesota, which is kind of what you’re spitballing. My thinking is that we have two swaps, but can only execute one.

I generally agree with this, but to play devil's advocate, using Chinook's example where MIN finishes with the 2nd draft seed, SAS 9th and DAL 30th, we could execute the swap with DAL, which DAL agreed to, and #30 becomes our pick. We could then SWAP with MIN, which MIN also agreed to in practical terms, because #30 is now ours (not DAL's).

Like I said, I agree with your impression, because that seems both logical and fair, but I can find an argument for the alternative. I'm gonna scan the CBA here in a few minutes, though I'm not sure it would be contained there since it doesn't directly involve players... I wonder if there is some other NBA rule book that deals with trades and procedure somewhere.

scott
07-23-2024, 10:07 PM
Well that was a quick scan... the CBA doesn't contain the word "swap" anywhere in it, so that's a dead end :lol

I'll see if I can find trade rules somewhere. The Salary Cap FAQ here has a little discussion, but not much: http://www.cbafaq.com/salarycap.htm

scott
07-23-2024, 10:14 PM
Frankly, I'm not sure that there is another example before SA30 where a team has held multiple swaps in the same year. I can't find anything where anyone has even contemplated these scenarios before.

rankingtear
07-23-2024, 10:54 PM
Frankly, I'm not sure that there is another example before SA30 where a team has held multiple swaps in the same year. I can't find anything where anyone has even contemplated these scenarios before.

OKC and UTA.

Seventyniner
07-23-2024, 10:58 PM
Frankly, I'm not sure that there is another example before SA30 where a team has held multiple swaps in the same year. I can't find anything where anyone has even contemplated these scenarios before.

Stacking swaps might be the next iteration of PATFO trying to be a step ahead of the league.

scott
07-23-2024, 11:11 PM
OKC and UTA.

Any specific years you are referring to? The Spurs are the only team who currently have multiple swaps in a future year. Lots of teams have swaps (and there have been 30-something swaps that have come and gone in the past, about a dozen of them finishing "in the money"), but I'm unaware of a team holding multiple in one year (and data is hard to come by)

scott
07-23-2024, 11:13 PM
Stacking swaps might be the next iteration of PATFO trying to be a step ahead of the league.

Yeah, I was just thinking that - especially if there are not clear rules about how they are handled and the Spurs can gain the unintended consequence of holding another team hostage so you don't jack with their draft position. Fascinating case here. I sent Keith Smith from Spotrac a note to see if he is aware of a Trade Rulebook or if he knows how these scenarios are dealt with, I'm hoping he will respond.

rankingtear
07-23-2024, 11:29 PM
Any specific years you are referring to? The Spurs are the only team who currently have multiple swaps in a future year. Lots of teams have swaps (and there have been 30-something swaps that have come and gone in the past, about a dozen of them finishing "in the money"), but I'm unaware of a team holding multiple in one year (and data is hard to come by)

OKC 25, HOU & LAC. UTA 26, MIN & CLE

Chinook
07-23-2024, 11:37 PM
We agreed to a swap with Dallas last summer, but they never agreed to swap with Minnesota, which is kind of what you’re spitballing. My thinking is that we have two swaps, but can only execute one.

Dallas never agreed to swap with Minny. We know that. That's why they're step one in the decision tree. But Minny's swap came after Dallas. It's definitely made with that knowledge in mind, even though it might not be truly nested. We don't know if the Spurs could trade with Dallas to extinguish their 2030 swap without affecting the Wolves. They should be able to do so if the swaps aren't considered to be dependent on each other.

That could lead to a case where the Wolves have a high pick, but the Spurs choose to swap with Dallas' lower pick to deny the Mavs a certain player. Like if Minny had 2, Dallas had 3 and SA had 30, the Spurs could take away Dallas' third-overall pick to deny them a lotto talent and allow the Wolves to keep the second pick. That seems spiteful, but Minny might be willing to toss a pick to the Spurs to extinguish their swap and tell the Spurs they don't intend to take a player SA wants.

An analogous hypothetical would be if the Spurs had swap rights to BRK24 and WSH24. The Spurs might have been able to choose to take Sheppard away from the Rockets and let the Wizards draft Sarr or Risacher in exchange for that 2029 first Portland traded them in the Avdija deal. Because the Spurs wouldn't want Sarr anyway, there's no downside to them doing so. Of course, swaps have to be executed earlier in the process, but the idea is still on the table.

As scott pointed out, there isn't much in terms of official language I found that explains how the process works. There have been opposite swaps than this, both where a team has offered swaps to multiple teams and where a team has agreed to swap multiple unprotected picks in the same year like with OKC. As far as I know, this is a new situation.

scott
07-24-2024, 01:08 AM
OKC 25, HOU & LAC. UTA 26, MIN & CLE

Gotcha, I see those now. The OKC25 is a little complicated because the protections are a little more strict. Are you aware of any circumstances like this that have already passed?

exstatic
07-24-2024, 05:11 AM
The Utah swap is stated as an OR. They make one swap.

The OKC one is more complicated. One of the swaps is with Houston, who has set up a further swap with BKN. Basically Houston gets to swap whatever pick they wind up with, theirs or OKCs, to BKN for a PHOENIX pick. They’re still not moving swaps around like chess pieces, though. OKC does their swap decision making OR algorithm, then after that, Houston does theirs.

rjv
07-24-2024, 12:31 PM
after reading this I came to the epiphany that ST, for all its faults, has to be one of, if not the best, basketball fan sites in all the NBA. I mean, on what other site will you see someone post a dissertation on how to quantify the value of draft picks? solid post, btw.

scott
07-24-2024, 01:18 PM
Thanks for the props rjv - I agree, when folks are fighting over what really just amounts to a divergence of opinion, this site does have some really sharp basketball folks and it quite a blast!

On another note, Keith Smith responded to me and said that things like this would be governed by the NBA Operations Manual, which is not public. He said that typically, when the trade is made, it will be specified how it will play out (for example, SAS and MIN may conduct a swap after SAS and DAL already has one that may explicitly state that SAS has the right to swap with the best of MIN/DAL, or it may even state that the Spurs will have the right to swap with the best of MIN/DAL and if they do so, MIN will get the 2nd best of what remains, etc.). It seems like it would be an uncommon occurrence for it to not all be specified in advance so that a team like SAS could reshuffle the order however they want at the moment.

exstatic
07-24-2024, 03:35 PM
Thanks for the props rjv - I agree, when folks are fighting over what really just amounts to a divergence of opinion, this site does have some really sharp basketball folks and it quite a blast!

On another note, Keith Smith responded to me and said that things like this would be governed by the NBA Operations Manual, which is not public. He said that typically, when the trade is made, it will be specified how it will play out (for example, SAS and MIN may conduct a swap after SAS and DAL already has one that may explicitly state that SAS has the right to swap with the best of MIN/DAL, or it may even state that the Spurs will have the right to swap with the best of MIN/DAL and if they do so, MIN will get the 2nd best of what remains, etc.). It seems like it would be an uncommon occurrence for it to not all be specified in advance so that a team like SAS could reshuffle the order however they want at the moment.

It’s frustrating that realgm hasn’t updated their future picks page.. It’s almost August, for chrissakes.

poopbox
07-24-2024, 07:15 PM
I would hope the point of all these future swaps is to cash them in for real star player next to Victor. If we actually end up making these selections in 2030 and 2031 something has probably gone terribly wrong.

exstatic
07-24-2024, 07:51 PM
I would hope the point of all these future swaps is to cash them in for real star player next to Victor. If we actually end up making these selections in 2030 and 2031 something has probably gone terribly wrong.

Not necessarily. At that point, we may need to cash out secondary stars for younger, cheaper talent due to the second apron.

TheChillFactor
07-25-2024, 10:28 AM
this is really dope Scott, and a lot of work.

i have thought for a while that the Spurs must have some sort of analysis like this that shows that with enough picks/swaps from different teams- small bets placed all over the league - there is an X% probability that one of those lands in the lottery, or the #1 pick, or top 5 or whatever.

At one point in my life I had the skills for this kind of analysis but those have been lost over time as I don't use them and I am old and have forgotten so much. You took the time and applied your knowledge to this idea and I appreciate all the work you did.

It would be interesting to apply this kind of analysis retroactively to Duncan's career. Imagine he had a top 5 pick joining the team in 2004, or lottery pick in 2006, or the #1 pick after winning a title. They have seeded Wembanyama's future with picks - you can also imagine if LeBron or Shaq or any other top level player had that kind of future mapped out for him.

This is too complex for the "Fire Brian Wright" crowd to understand. Well done.

scott
07-25-2024, 01:36 PM
this is really dope Scott, and a lot of work.

i have thought for a while that the Spurs must have some sort of analysis like this that shows that with enough picks/swaps from different teams- small bets placed all over the league - there is an X% probability that one of those lands in the lottery, or the #1 pick, or top 5 or whatever.

At one point in my life I had the skills for this kind of analysis but those have been lost over time as I don't use them and I am old and have forgotten so much. You took the time and applied your knowledge to this idea and I appreciate all the work you did.

It would be interesting to apply this kind of analysis retroactively to Duncan's career. Imagine he had a top 5 pick joining the team in 2004, or lottery pick in 2006, or the #1 pick after winning a title. They have seeded Wembanyama's future with picks - you can also imagine if LeBron or Shaq or any other top level player had that kind of future mapped out for him.

This is too complex for the "Fire Brian Wright" crowd to understand. Well done.

Thanks!

I will admit, that some of my stats skills are a little rusty as well - I've found AI (I use MetaAI, because it doesn't limit your usage like the free version of ChatGPT does) quite helpful. I essentially trained the AI with prompts to understand the circumstances, then asked some probing questions on calculating some probabilities, then asked it to show me how to do it in Excel. It had been probably a decade since I've used the COMBIN function in Excel, and once I was reminded of that (and how it basically provides you with the possible outcomes for a given scenario), building the rest of the probability chart was a breeze.

While I'm confident that AI will be the end of humanity, at least it can help me with some fun analysis in the meantime :lol

TheChillFactor
07-25-2024, 02:30 PM
Thanks!

I will admit, that some of my stats skills are a little rusty as well - I've found AI (I use MetaAI, because it doesn't limit your usage like the free version of ChatGPT does) quite helpful. I essentially trained the AI with prompts to understand the circumstances, then asked some probing questions on calculating some probabilities, then asked it to show me how to do it in Excel. It had been probably a decade since I've used the COMBIN function in Excel, and once I was reminded of that (and how it basically provides you with the possible outcomes for a given scenario), building the rest of the probability chart was a breeze.

While I'm confident that AI will be the end of humanity, at least it can help me with some fun analysis in the meantime :lol

someday when i have time i wanna go back and do a crude analysis of who we would have had available to us to draft if we had the same picks/pick swaps for the same teams in Duncan's career.

That would make a fun article for one of these hack sites to put together.

TeKu
08-06-2024, 03:38 PM
Late to this thread sorry, but did want to say thanks to scott for compiling this, great stuff.

If the FO is half as smart as you here then this would explain why the SAC swap was in 31 rather than 30 also, which I questioned at the time.

By your numbers, and additional 2030 swap (to add to MIN/DAL) adds 7.2% odds of a lottery pick (+10.5% of a top 5 pick though), while adding that swap in 2031 instead adds 25.7% odds of a lottery pick (+14.3% of top 5 pick), albeit to lower odds overall. Which might indicate what the FO is actually valuing over that timespan also (regular lottery picks over a single high pick).

Handy numbers to check back on again given Wrights love of swaps. Thanks.

scott
08-06-2024, 04:10 PM
Thanks TeKu!

One note - a Jazz redditor vehemently argued with me over the tradability of acquired swaps (when coupled with team's original draft picks). I am confident that you can indeed trade swaps this way (for example, you send Team X the better of SA/ATL26, with ATL maintaining the worst of the two picks) - however I cannot find any definitive written confirmation that this is the case. The redditor argued that if SA traded it's 26 pick (for example), the swap with ATL would simply be extinguished, which makes no sense. That person's major argument that couldn't point to an example of a trade like what propose happening in the past, so it "must not" be allowed. He also argued that (for example) ATL didn't agree to swap its pick with Team X, only with the Spurs. That should be irrelevant, because ATL's results from the swap don't change, regardless of who owns the Spurs pick.

It doesn't make sense that an asset (an acquired swap) would simply vanish into thin air if you traded away another asset (your pick). Does anyone have examples of a team trading away its pick with swaps attached? If you can't do that, then swaps are significantly less valuable (because they only maintain value if you hold them), but I don't believe this to be the case.

Mal
08-06-2024, 04:22 PM
I am late to this. So the conclusion is that having two swaps in same years, boost chances for lotto pick significantly ?

scott
08-06-2024, 04:27 PM
I am late to this. So the conclusion is that having two swaps in same years, boost chances for lotto pick significantly ?

Basically yes, if you believe in one pretty important assumption: that team outcomes far out in the future are basically random, which tends to more or less be backed up by the data.

However, if you believe in more dynastic team results based on superstars, then having the best of a pick between teams that have Wemby, Luka and Ant may not be all that impressive.

TeKu
08-06-2024, 04:30 PM
It doesn't make sense that an asset (an acquired swap) would simply vanish into thin air if you traded away another asset (your pick). Does anyone have examples of a team trading away its pick with swaps attached? If you can't do that, then swaps are significantly less valuable (because they only maintain value if you hold them), but I don't believe this to be the case.

Would think the 2028 PHO swap they traded to WAS in the Bradley beal trade is an example here? My understanding is that BKN have the first right to swap either their pick or PHI pick (which may convey that year) with PHO first, and then WAS gets the rights to swap their pick with whichever pick PHO holds at that point. I'm not 100% on that at all, but would definitely suggest that pick swaps can be included/accounted for in a trade.

spurraider21
08-06-2024, 05:08 PM
Thanks TeKu (https://www.spurstalk.com/forums/member.php?u=449)!

One note - a Jazz redditor vehemently argued with me over the tradability of acquired swaps (when coupled with team's original draft picks). I am confident that you can indeed trade swaps this way (for example, you send Team X the better of SA/ATL26, with ATL maintaining the worst of the two picks) - however I cannot find any definitive written confirmation that this is the case. The redditor argued that if SA traded it's 26 pick (for example), the swap with ATL would simply be extinguished, which makes no sense. That person's major argument that couldn't point to an example of a trade like what propose happening in the past, so it "must not" be allowed. He also argued that (for example) ATL didn't agree to swap its pick with Team X, only with the Spurs. That should be irrelevant, because ATL's results from the swap don't change, regardless of who owns the Spurs pick.

It doesn't make sense that an asset (an acquired swap) would simply vanish into thin air if you traded away another asset (your pick). Does anyone have examples of a team trading away its pick with swaps attached? If you can't do that, then swaps are significantly less valuable (because they only maintain value if you hold them), but I don't believe this to be the case.
yeah, thats nonsense

we see ALL the time, when a team trades for "the most favorable" or "least favorable" of some set of picks. that is only possible if a swapped pick is being traded.

exstatic
08-06-2024, 05:32 PM
Would think the 2028 PHO swap they traded to WAS in the Bradley beal trade is an example here? My understanding is that BKN have the first right to swap either their pick or PHI pick (which may convey that year) with PHO first, and then WAS gets the rights to swap their pick with whichever pick PHO holds at that point. I'm not 100% on that at all, but would definitely suggest that pick swaps can be included/accounted for in a trade.

That wasn’t all the result of one trade. Phoenix traded fractional swaps of the same pick with different protections.

Pauleta14
08-06-2024, 06:12 PM
Way to take advantage of "a little bit of downtime" scott !! :lol :bobo

scott
08-06-2024, 08:25 PM
Way to take advantage of "a little bit of downtime" scott !! :lol :bobo

Haha. I've been very fortunate in life, which allows me to do things like waste time thinking about the Spurs, collect basketball cards (I've got quite the valuable Wemby collection amassing) and do stupid stats experiments :lol

exstatic
08-30-2024, 05:08 PM
In the non-basketball world, it would all depend on how the contract is written... but since I've never worked in an NBA front office I don't know how these things are actually negotiated/done. Take the hypothetical where we are discussing acquiring a 2030 swap from Miami. I'd presume we can write this any way the two teams agree upon. Miami can give us the right to swap any pick we have... or Miami can agree to swap us with the Spurs natural pick... or Miami can agree to swap their pick with the next best of SAS/DAL/MIN? Of course... all subject to whatever rules the league has set forth.

Surely the NBA must have a written rule, right? It makes perfect sense that we would only be allowed to do one swap... but does it explicitly state that anywhere?

RealGM has updated the future owed picks page. This is what they have to say.


2030 first round draft pick from Dallas or Minnesota (San Antonio outgoing to Dallas or Minnesota)
San Antonio will receive the most favorable of its 2030 1st round pick, Dallas' 2030 1st round pick and Minnesota's 2030 1st round pick protected for selection 1; Dallas will receive the less favorable of its pick and the San Antonio pick; Minnesota will receive the less favorable of (i) its pick and (ii) the more favorable of the San Antonio pick and the Dallas pick; if the Minnesota pick falls on its protected selection, then Minnesota's obligation to San Antonio will be extinguished and San Antonio will instead have the right to swap its pick for the Dallas pick (via San Antonio's right to swap for Dallas; via San Antonio's right to swap San Antonio or Dallas for Minnesota) [Boston-Dallas-San Antonio, 7/12/2023; Minnesota-San Antonio, 6/26/2024]

Brazil
09-03-2024, 04:12 PM
I was vacationing when you posted this thread scott, I just saw it today.. that's some awseome work, quite interesting to understand some teams recent obsession with pick swaps :tu

Russ
09-06-2024, 11:25 AM
Stacking draft pick swaps might create a psychological high, but it doesn’t seem to change your chances of getting a good pick -- it all washes out in the end (at best).

Using your example:



As you can see, in 2030, when the Spurs have two swaps (ignoring the protections), they have a 86.2% chance of our pick ending up a lottery pick. That makes that pick extremely valuable, because otherwise a pick with no swaps would only have a 46.7% chance of being a lottery pick.

However, on the other hand, if you used those two draft swaps in different years you would have two 72.4% chances of getting a lottery pick or a cumulative 144.8% chance over two years.

If you stack the picks you correctly point out that you have an 86.2% chance of getting a lottery pick in the stacked year but you also have only a 46.7% chance of getting a lottery pick in the other year for a lesser total two-year chance of 132.9%.

That’s not stacking assets, it seems more like diminishing returns.

Say you get really radical and you can take four swaps in one draft or one swap in each of four drafts.

According to the chart you have a 96.9% chance of getting a lottery pick in the four-stacked draft and a 46.7% in the other three. That’s a total of 237% divided by four or 59.25% per year.

On the other hand, you could simply get four years at a higher 72.4% per year if you just take one swap per year.

So the more stacking you do, the worse it gets if you just want a lottery pick (according to the chart).

Actually, the more favorable argument for stacking swaps is the chance of getting the number one pick. But even then, it’s just a statistical wash.

If you can stack two swaps in one year or one swap in each of two years, according to the chart, you get a 10% chance at the No. 1 pick in the two-stacked year and a 3% chance in the other for a 13% total.

Or two years (with one pick swap) at 6% for a 12% total.

(That’s statistically identical because the difference is due to a slight rounding error on the chart, the 3% chance of getting the 1 pick with no swaps should be 3.33% (correctly rounded to 3%), the chance with one swap should be 6.66% (slightly incorrectly rounded to 6%) and with two swaps it should 9.99% (correctly rounded to 10%).)

In the end, the sad statistics indicate a wash. No free lunches as it turns out.

Stacking draft pick swaps might create a psychological high, but it doesn’t change the math.

In fact, stacking pick swaps may be like having money for two lottery tickets and deciding to buy two today rather than one today and one tomorrow.

In the end, as we all know, it probably won’t matter.

And ultimately in the end, thanks, scott, for your thought-provoking contribution during this long off-season.

stnick2261
09-06-2024, 11:40 AM
However, on the other hand, if you used those two draft swaps in different years you would have two 72.4% chances of getting a lottery pick or a cumulative 144.8% chance over two years.

If you stack the picks you correctly point out that you have an 86.2% chance of getting a lottery pick in the stacked year but you also have only a 46.7% chance of getting a lottery pick in the other year for a lesser total two-year chance of 132.9%.

That’s not stacking assets, it seems more like diminishing returns.

Stacking swaps is definitely diminishing returns... however, it's also diminishing costs. Teams are more willing to trade a swap (cheaply) to a team that already has a swap because it's a lower chance of conveying.

Russ
09-06-2024, 11:44 AM
Stacking swaps is definitely diminishing returns... however, it's also diminishing costs. Teams are more willing to trade a swap (cheaply) to a team that already has a swap because it's a lower chance of conveying.

Good point.

scott
09-06-2024, 02:20 PM
Say you get really radical and you can take four swaps in one draft or one swap in each of four drafts.

According to the chart you have a 96.9% chance of getting a lottery pick in the four-stacked draft and a 46.7% in the other three. That’s a total of 237% divided by four or 59.25% per year.

On the other hand, you could simply get four years at a higher 72.4% per year if you just take one swap per year.

So the more stacking you do, the worse it gets if you just want a lottery pick (according to the chart).

Actually, the more favorable argument for stacking swaps is the chance of getting the number one pick. But even then, it’s just a statistical wash.

If you can stack two swaps in one year or one swap in each of two years, according to the chart, you get a 10% chance at the No. 1 pick in the two-stacked year and a 3% chance in the other for a 13% total.

Or two years (with one pick swap) at 6% for a 12% total.

(That’s statistically identical because the difference is due to a slight rounding error on the chart, the 3% chance of getting the 1 pick with no swaps should be 3.33% (correctly rounded to 3%), the chance with one swap should be 6.66% (slightly incorrectly rounded to 6%) and with two swaps it should 9.99% (correctly rounded to 10%).)

In the end, the sad statistics indicate a wash. No free lunches as it turns out.

Stacking draft pick swaps might create a psychological high, but it doesn’t change the math.

In fact, stacking pick swaps may be like having money for two lottery tickets and deciding to buy two today rather than one today and one tomorrow.

In the end, as we all know, it probably won’t matter.

And ultimately in the end, thanks, scott, for your thought-provoking contribution during this long off-season.

There are absolutely diminishing marginal returns, and of course the chart kind of points that out, but that is a great call out.

I did want to address a little bit of math that you call out here (since you can't just sum up and divide probabilities to be statistically correct, but your points all remain valid)...

If you assume natural variance and a 46.7% chance of a lottery pick in any given far future year (which is certainly debatable), then every team naturally has a 91.9% chance of at least one lottery pick over a 4 year stretch. If you had one swap each year over a 4 year stretch (meaning a 72.4% chance at a lotto pick each year over 4 years), then you would have a 99.4% chance of at least one lotto pick over 4 years (!!!).

So if your goal is to get a lotto pick over a period of time, then horizontal stacking of swaps makes more sense, but if your goal is to get a lotto pick in a certain year (maybe you want 2031 because some contracts will be expiring and that is the year you want it, or you've scouted some 11 year old, or whatever), then vertical stacking is the way to go.

Great points, Russ.

Russ
09-06-2024, 05:19 PM
So if your goal is to get a lotto pick over a period of time, then horizontal stacking of swaps makes more sense, but if your goal is to get a lotto pick in a certain year (maybe you want 2031 because some contracts will be expiring and that is the year you want it, or you've scouted some 11 year old, or whatever), then vertical stacking is the way to go.

Yeah, stacking can make sense in a particular situation that would have to be gamed out with factors unique to that draft, e.g., your likely lotto position, that of your partner and the tier distribution within that draft class.

Your chart was based upon an abstract neutral distribution of draft chances, which was really the only principled way to do it for discussion.

Dex
09-07-2024, 06:25 PM
Great post, scott!

Next season will be very telling for the Spurs and their direction, but for a team not expected to contend this season, we seem to be in good shape.

✔ Young superstar and potential generational player (Wemby)
✔ Several young developing players with promise on decent contracts (Vassell, KJ, Sochan, Branham, Jones, Wesley, Castle)
✔ Veteran players with expiring contracts (CP3 and Barnes)
✔ Players that are easy to dump or include in a trade if needed (Collins, Champ, Bassey, Mamu)
✔ Tons of draft assets spanning the next 6 years

This year should establish our timeline. I still think we are 2 years from being a true playoff team, but we'll see what happens.

ZeusWillJudge
09-08-2024, 05:36 AM
That's really good work. Sincerely. I haven't done a dive to confirm the numbers, but it feels like I'm seeing more swaps being used in the last few years. Maybe that's because teams started getting raw over protected swaps that wind up conveying as second rounders. That's a terrible ROI for teams that actually trade away an asset, and they are so subject to manipulation. With a swap, tanking would harm your own team as much as the other one. But I still don't like them, and don't think they offer very much in the way of value. After seeing Russ's post above, I'm not going to bother saying what I was going to say. But the worst of the worst are the protected pick swaps, and I can't believe anyone would accept one of those except when the trade is really just a salary dump, and getting a swap is sort of taking a flyer that you might get to move up a couple of spots in the middle of the draft. And not for nothing, I think the biggest reason we used to see them is because of the Stepien Rule. Now they seem to be getting used more often than just that. (That's just a gut belief - I'm not going to try and run down season by season pick swaps.)

Personally, I wouldn't give them as much value as you did. I would much rather have a high second round pick than a swap that might wind up being vapor. There are often some solid players that fall just out of the first round. And even though you're taking a chance on a player that fell out of the first round, second rounders don't come with guaranteed contracts. Second round picks aren't subject to Stepien, so you could demand a second round pick for, say, 2025 or 2026 and not have to worry that the other team is going to tank, because they wouldn't damage their first round pick to try and hang onto their second rounder. There's still no guarantee that you get a high second round pick, but at least you know you get something.

I understand your math. But if you look at a swap as an asset, if you stack them in a single year you pretty much have to cut the value of each one in half because you know you can't use them both. Stacking two swaps doesn't double your chance of getting a lottery pick, so I think it's a mony loser overall. If you really want to juice your analysis, factor in EV of lottery picks (especially at the end of the lottery), guaranteed contracts, etc. Then go sell yourself as the Paul DePodesta of basketball and retire early. But get Russ to help you with it.

scott
10-31-2024, 09:05 PM
Something I didn't include in my original post because it should have been obvious... but suddenly seems important to point out:

Pick swaps hold zero value when you are considerably worse than all the teams you've swapped with.

Guru of Nothing
10-31-2024, 09:10 PM
Something I didn't include in my original post because it should have been obvious... but suddenly seems important to point out:

Pick swaps hold zero value when you are considerably worse than all the teams you've swapped with.

Newman!

CorrectCrusader
10-31-2024, 10:26 PM
Fantastic post.