Inflation generally
A key concept for keeper leagues is inflation. Because some players are kept at a cost less than their expected value, the remaining players will, on average, cost more than their expected value. Keepers are good deals, making everyone else bad deals.
This is obvious in auction leagues, where player costs are literal dollar values. Inflation might cause non-keepers to cost, for example, 25% more than in a league without keepers. Knowing this number, at least to an approximate degree, going into the auction helps you make sure you aren’t accidentally bidding too much or too little and ending up with a bunch of players you don’t actually want. It’s also critical for deciding on your keepers.
Inflation is less obvious in draft leagues, maybe because it’s a less common format, or maybe because there aren’t (necessarily) literal dollar values involved. What does it even mean for the cost of a player to be inflated when measured in draft rounds? And what can you even gain by understanding the degree to which draft inflation is occurring? After all, you still have the picks you have, and don’t have to navigate auction dynamics.
If you want the philosophical stuff first, keep reading. If you want to jump to the nerdy math stuff first, jump to the section titled “How to calculate inflated values in keeper leagues.)
What does inflation even mean in draft keeper leagues?
Note: in lieu of potentially confusing everybody trying to figure out what I mean by higher and lower draft picks (does higher mean a higher number or an earlier pick?) I’m going to use “earlier” and “later” in this article. Yeah, a bit awkward, but hopefully more clear.
Draft keepers are kept with worse picks than they would have been drafted at in a redraft league. E.g. a first round pick is kept with a fifth round pick, or a tenth round pick is kept with a 20th round pick. That takes a lot of good and mediocre players off the board, and a lot of mediocre and bad draft picks off the board. What’s left is better picks for worse players. Instead of there being 15 first-round caliber players to be had with 15 first-round picks, there are, maybe, ten available. That means five first round picks will go to second-round caliber players. Or when you get down to the fifth round, those picks might net you eighth-round production.
Because of inflation, draft picks are providing worse production. Perhaps a better term for things viewed this way is deflation. The value of each draft pick is deflated. You get less bang for your buck. Put back in terms of inflation, the cost of production has gone up. Tenth-round talent is costing a fifth round pick, and some second-round talent is costing a first-round pick.
Why should I care? Why is knowing keeper inflation useful?
Inflated keeper values help you make better keeper decisions
Sure, you could just compare keeper rounds with redraft rounds and keep the largest gaps, but that misses two things:
The gap between rounds is not the same as you get later in the draft. Fortunately, this can be easily addressed by converting draft rounds into draft dollars. As discussed later in the technical stuff, dealing with the continuous scale of draft dollars makes everything easier and correctly accounts for pick and player gaps.
More importantly, keeper evaluation should compare the cost of a keeper to what the alternative would be in the actual, inflated draft, not in a theoretical uninflated draft. In auction leagues, a $20 keeper expected to provide $18 of production seems like a bad deal, but if inflation pushes their in-auction cost up to $22, then they are actually worth keeping. If a player can be kept with an Xth-round pick, you want to know what will actually be available in round X after all the keepers are taken out. In general, doing this will make good players with better keeper rounds more valuable keepers.
Inflated keeper values help with keeper trades
Better knowing keeper values also helps you discuss trades with other teams. You can take advantage of other teams that don’t see keeper value the way you do. You can also be more confident in the precision to which you value players, proposing more small-margin trades. Every little bit counts, and a few small trades can have just as much of an impact as a big trade that the other team probably doesn’t want to do anyway.
Related, you have a better framework for 1-for-2 and 2-for-1 trades. 2-for-1 trades are generally better, as you get a better keeper and get to promote someone beyond your keeper limit into a keeper slot. But with weaker or top-heavy keeper lists, taking one downgrade for two similarly-sized upgrades can be worth it. In either case, just make sure to include the players promoted/demoted from your keeper list in addition to the traded players when evaluating the trade.
Inflated keeper values help with draft pick trades
This one is my favorite. Trades are fun, and draft picks become something else you can trade in draft keeper leagues. Some teams want to move up in the draft, some teams want to move down. As part of calculating draft inflation, you know what every draft pick is worth, so you can be willing to trade in both directions as long as it’s worth it for you. Maybe you’d give up a first and eighth for a second and fourth, but would only give up a fourth and third for a first and seventh. There are now twice as many teams to trade with.
Inflated keeper values help when choosing which team to take over in an existing keeper league.
This one’s straight forward. Better data makes for better decisions.
How to calculate inflated values in keeper leagues
Start with a list of players and their dollar values. Depending on roster sizes, number of teams, player eligibility, and scoring rules, there is a unique value for each player. A $1 player represents the worst player worth picking, and the best players can be worth $40+ depending on the league. In general, a $30 player is as productive as two $15 players. In geekier terms, dollar values create a ratio scale for players.
(Yes, there are ways to convert ADP to dollar values, but most of the time it’s better to just start with auction values. Free options include Fangraphs and Draftkick. These tools also make sure the dollar values are customized to your league rules, which is a great way to avoid screwing up your season before it even starts.)
To the dollar values, add the team that could keep each player, and the round in which they would be kept.
Once you have your dollar values, calculate the average dollar value available in each round (ignoring keepers for now.) Sort the players from best to worst, then put the expected round next to each player — 1’s then 2’s then 3’s etc. (Use formulas, please do not tell me you did this manually.) Maybe the top five rounds look something like $40, $30, $22, $15, $9.
Now, for each player, compare the value of the round they can be kept to their actual dollar value. This is the first iteration of keeper value. Higher numbers are better keeper values, where the production most outweighs the cost. Sort this value from best to worst, and then sort by team. (Some players won’t be on teams, ignore them for now.)
Go through each team and, in a new column, mark which players you think each team will keep. Usually the number of keepers per team has a cap, so just mark everyone from the top down until you reach that cap or players with negative keeper value. Don’t overthink this, but if you know your league in general, or owners specifically, are more or less likely to keep certain types of players (first-rounders, pitchers, rookies, whatever) then you can make some manual adjustments. (This is where trade conversations with other teams can come in extra handy, by learning which players they are actually likely to keep.)
We’re not done! We haven’t actually calculated inflation yet! The next step is to re-value each round based on who is NOT a keeper, and then calculate a second iteration of keeper value.
Calculate how many players are being kept in each round, and thus the number of players to be picked in each round. Sort the player list from best to worst, then filter out the keepers. Given the number of players remaining in each round, assign rounds to players again. I still recommend using formulas, but it’s definitely trickier at this stage. (Manual is now acceptable.) Do the calculation of what a pick in each round is worth again, based on the second iteration of draft rounds. Each round will be lower, maybe something like $35, $26, $19, $13, $8.
Unfilter the list, calculate each player’s keeper values using the new round values, then repeat the process of sorting keepers from best to worst by team in a new column. Chances are that *most* keepers don’t change, but some likely will — again, players with early-round keeper costs will gain value.
If you like, you can repeat the process of updating expected round value based on keepers, but I’ve found the third iteration provides significantly less value than the second iteration.
Boom! Now you’ve got a list of expected keepers by team, relative keeper value for all players, and the expected value of a draft pick in each round. Definitely worth it.
You could also do all of this math on the pick level (instead of round level). More complex, but more precise, potentially. You decide if it’s worth it, I’m not going to throw a “definitely” out for this method.
First-round exception
While averaging the players available in each round is more than fine, it’s probably worth valuing the first 4-6 picks individually. How many of those picks are non-keepers, and who is the best non-keeper available at each slot? The top of the first round is not only much better than the bottom of the first round, there’s often 1-3 top-tier non-keepers that make the first few picks worth a lot, although this is highly league and year dependent. It’s useful to keep this granular value of the first round in mind when deciding on keepers and trading for draft picks. For example, Aaron Judge is a much better keeper in the bottom of the first round than at the top of the first round. And if the top three non-keepers are Judge, Witt and Vlad, you’d much rather have one of the first two real picks than the third.
Resources
If you’re interested in making more trades because of this post, check out my post on fantasy baseball trading tips.
I really like discussing this topic (anything feel free to ping me at Blue Sky, via email (skyking162 at Gmail), or in Substack comments/notes.
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