The IATF would like to officially announce a clarification to our definition of league sanctioned target designs.
While flatboard construction is the recommended standard, we are happy to include end-board constructed targets, stumps, or targets created via projector, only so long as these targets strictly conform to the IATF guidelines regarding the placement and measurements of the target rings and Clutches, as well as being positioned the appropriate distances and heights from our sanctioned throwing and safety lines.
We felt this clarification appropriate given the strains certain clubs have been under to meet the letter of our league standards while simultaneously confronting supply chain issues and rising material cost over the past two years.
If any organization or thrower has further questions, please consult the official IATF rulebook here.
Over a year ago the International Axe Throwing Federation (IATF) launched the Collins Rating System. This system is based on the Elo rating system widely used in chess, online gaming and other kinds of head-to-head competition. The system considers the level of stakes at hand as well as the value of one-on-one competition, and has been adapted by the IATF to accommodate the complexities of axe throwing. The Elo system was selected because it ranks players in head-to-head competition through a mathematical equation.
This system works well for the IATF. We value head-to-head competition, both in our sport and as sports fans, and see the value in a rating system that rates players according to skill and skill improvement. We operate in the spirit of fairness in competition; all venues operate differently, but still have an accurate system of rating for throwers across all IATF organizations.
Key Principles
- Head-to-head competition should be used to assess skills and determine ratings. (true since version 1.0)
- Beating lower rated players is less valuable than beating higher rated players. (true since version 1.0)
- Higher levels of competition should raise the stakes by allowing larger adjustments, if required to better reflect players’ relative skill. ie. IATC has higher stakes than Regionals which in turn has higher stakes than league playoffs. (true since version 1.0)
- Throwing an 81 and winning the tiebreaker should never result in a downward adjustment (this became clear from version 1.0)
- Throwing more frequently should not disproportionately inflate ratings (true since version 1.0, however version 1.1 created a deviation from this principle, version 1.2 addresses the inflation from version 1.1)
Reviewing How it Works:
Each players’ rating goes up or down at the end of a match based on the result of each round. Players have their rating compared to the rating of their opponent. If the higher rated player wins, as expected, adjustments are generally small. However, if the lower rated player wins, an adjustment in ratings moves both players’ ratings – up for the lower rated player, and down for the higher rated player.
CRS 1.0 – The first version of CRS adjusted players rating based on winning or losing rounds within a match. These adjustments were affected by the ratings of their opponents as well as the expected result going into the match.
For example, in version 1.0 (example A): Alice and Bob are throwing a match. Alice is a higher rated player than Bob. When Alice wins the match, her rating goes up slightly and Bob’s goes down slightly, by the same amount. However, if Bob (as the lower rated player) were to win the match, his rating would go up and Alice’s rating would go down, again by the same amount.
Another example (example B): A highly rated player who ties a lower rated player at 81 and wins the tiebreaker. Based on their rating before the match, the lower rated player has exceeded their expectation by taking the match to a tie breaker, and needed an upward adjustment. Since in CRS 1.0 the adjustments were always equal, but opposite, the higher rated player’s rating would be adjusted downward to match the lower rated player’s increase after the match. The result of which was that the two players were now more closely rated, which was the desired result of the system.
Transition to Version 1.1 – After listening to feedback from the community and observing how the System worked in a live setting, it was clear that the rating calculation was not performing as desired in some match scenarios. It was determined that the cause was that ties at 27 were being treated in the same manner as other ties, which, since this is the maximum score, felt like a penalty for the higher rated player, as outlined in example B, described in the previous paragraph. The natural question was “How could I have done better? Why would my rating go down in that scenario?”
Version 1.1 – To address how ties at 27 were impacting rating adjustments, a modification to the calculation was made to treat these rounds as a win in that round for both players instead of a tie in that round for both players; the rationale being neither player could have done better, so this should count as a win. This meant that in matches with ties at 27, it was now possible for both players to be adjusted positively since both players threw as well as possible in that round. This effectively created new “bonus” rating points, adding them to the system. It also meant that the lower rated players’ adjustments were greater than the higher rated players’.
This modification created a new issue wherein players who were tying at 27 more frequently, especially by throwing in multiple leagues, were receiving a disproportionate boost to their ratings since these “bonus” rating points threw off the original balance of the system. This effect was more pronounced for the lower rated players.
For example, in version 1.1 (example C): Alice and Bob are both rated 1600. Alice and Bob both throw 27s at the same percentage rate, however, Alice throws in one league and Bob throws in four leagues. Bob stands to gain four times the “bonus” rating points.
Following the release of Version 1.1, after listening to community feedback and observing actual match rating adjustments, it was clear that another modification would be needed to align the CRS to some key principles.
Version 1.2
A modification to the calculation was made that would treat ties at 27 as follows:
- The higher rated player’s round is treated as their expected result in the round. This means that it is no longer possible to tie at 81 and win the tiebreaker and have the rating adjusted downward.
- The lower rated player’s round is treated as a tie in the round (as with Version 1.0). It should be noted that a tie for the lower rated player is better than expectation. This means that throwing an 81 against a better player can result in a positive adjustment, even if the tie breaker is lost. However, it also avoids the inflated rating adjustments of Version 1.1.
For example, in version 1.2 (example D): Alice and Bob play a match. Alice is rated 1700 and Bob is rated 1500. Alice is expected to win. They both throw three rounds of 27 and tie overall at 81. Alice wins the tiebreaker.
The resulting rating adjustment for each of the CRS versions would be (see The Full Nerd Version below):
| CRS Version | Alice | Bob |
| 1.0 | -3 | +3 |
| 1.1 | +5 | +10 |
| 1.2 | +1 | +3 |
This particular case highlights the differences between the versions. CRS 1.2 produces adjustments that best align with the key principles behind the CRS.
Players should note that when version 1.2 is implemented there will be a shift in rankings. Multiple tests have been carried out to assess the accuracy of version 1.2 and our team has concluded that this latest version is the most balanced and fair while maintaining the key principles of head-to-head competition that we hold dear in our sport.
Version 1.2 will be launched on Friday July 17, 2020. For those interested in a more detailed understanding of the rating calculation please see The Full Nerd Version below.
Remote Matches
We are excited to launch the IATF AxeScores app soon, which will include a remote challenge feature. The app will increase players ability to seek out higher levels of competition across all IATF players. Players who would normally not be able to geographically play against each other on a regular basis will now be able to throw heard-to-head matches via the app. These matches will count towards CRS ratings at half of the value of regular league play. This reflects the principles of competition outlined above wherein we value higher profile matches and tournament at higher rating multipliers ie. Playoffs have higher stakes than regular league play which in turn has higher stakes than remote matches. This also reflects the level of supervision during those matches. Remote matches will be regulated using tools within the app. Because there is less oversight and officiating, the matches’ rating value will be less.
The Full Nerd Version – CRS 1.2
The procedure for calculating rating adjustments is as follows:
Let the initial rating of a player be pi and the initial rating of the player’s opponent be qi.
Let the player’s match expectation value be E. The expectation value is calculated as:
E= 2 / 1+10qi – pi / 400
It follows that pi >qi1 < E < 2 and pi<qi0 < E < 1.
Each round in the match is evaluated to determine the result. A win is valued at 1, a loss at 0 and a tie at 0.5. In the case of a tie at 27, if pi>qi the round is valued at half the expectation value (E/2).
The set of the player’s round results is g1,g2,…,gnwhere g1 is the player’s result in round 1 and gn is the player’s result in round n and n is the number of rounds.
Let the player’s match result value be R. The match result value is calculated as follows:
R=2nk = 1ngk, where n is the number of rounds.
Observe ∵ 0<gk<10<R<2.
Let the player’s rating adjustment be A. The adjustment is calculated as follows:
A=f*R-E, where denotes rounding to the nearest integer, and f*is a swing factor1.
Let the player’s final rating be pf. The final rating is calculated as follows2:
pf=pi+A
An example, for illustration:
Alice has a rating of 1700.
Bob has a rating of 1500.
Alice is the higher rated player, they are expected to win.
Alice’s expectation value is 2 / 1+101500 – 1700 / 4001.52.
Bob’s expectation value is 2 / 1+101700 – 1500 / 4000.48.
Alice’s expectation value is higher than Bob’s, since Alice is expected to win.
In round 1 Alice and Bob tie at 25.
In round 2 Alice wins 25-20.
In round 3 Alice wins 27-21.
Alice has won the match.
Alice’s round results are: 0.5,1,1.
Bob’s round results are: 0.5,0,0.
Alice’s match result is: 232.51.67.
Bob’s match result is: 230.50.34.
Alice’s adjustment is: 101.67-1.52 +1 (here 10 is the swing factor).
Bob’s adjustment is: 100.34-0.48 -1.
Alice’s rating after the match is 1701.
Bob’s rating after the match is 1499.
Since Alice won the match, and approximately by the expected amount, the adjustment is small.
Had the first round been a tie at 27 instead of 25, the results would follow:
Alice’s round results are: 0.76,1,1.
Bob’s round results are: 0.5,0,0.
Alice’s match result is: 232.761.84.
Bob’s match result is: 230.50.34.
Alice’s adjustment is: 101.84-1.52 +3.
Bob’s adjustment is: 100.34-0.48 -1.
Alice’s rating after the match is 1703.
Bob’s rating after the match is 1499.
Alice’s performance is a little better and the adjustment is a little greater. The tie doesn’t affect Bob differently though, a tie in this case is still better than their expectation.
Had Bob won rounds 2 & 3 (leaving the tie at 27), the results would follow:
Alice’s round results are: 0.76,0,0.
Bob’s round results are: 0.5,1,1.
Alice’s match result is: 230.760.51.
Bob’s match result is: 232.51.67.
Alice’s adjustment is: 100.51-1.52 -10.
Bob’s adjustment is: 101.67-0.48 +12.
Alice’s rating after the match is 1690.
Bob’s rating after the match is 1512.
Bob performed much better than expected and Alice performed worse. Their rating adjustments reflect the upset.
It should be noted that the first 28 matches a player completes in their career have an additional consideration, specifically, opponents’ ratings in these 28 matches are not adjusted unless the match is also one of the opponents’ first 28 matches. This prevents the uncertainty of new players’ ratings from affecting their opponents’ ratings in their first career season.
1 The swing factor f*is a parameter chosen to reflect the stakes of the type of match. The swing factor acts as a bounding factor on how large a rating adjustment can be for any given match of that type. Observe A<2f*. The swing factor generally increases with the level of competition or tournament profile. Regular league play has a swing factor of 10, larger tournaments can have swing factors of up to 20.
2 The calculation can be expressed in terms of source input values as:
pf=pi+2f*1nk = 1ngk-1+10qi – pi / 400-1
Definitions
where
pf is the player’s final rating,
pi is the player’s initial rating,
qi is the opponent’s initial rating,
f*is a swing factor,
gk is the player’s result in round k,
n is the number of rounds,and denotes rounding to the nearest integer.
Hello everyone,
Since the debut of our Premier Ruleset we’ve paid close attention to the feedback from our Premier League players as well as the rest of the axe throwing community. While Premier Leagues have accomplished several of the key goals we identified when constructing the ruleset, we believe that no ruleset is free from the ability to grow and improve.
The move from majority scoring to ‘no bleed’ scoring for standard throws was a logical progression for our more advanced throwers competing in Premier Leagues, and the shrinking of the clutch to 2 inches on all targets was shown to be necessary in both Standard and Premier streams where ‘going for clutch’ was beginning to lose its sense of challenge.
While our clutch requirements for Premier have had the desired effect in regards to bringing successful clutch attempts made by high level players down, making them harder to hit and, therefore, more exciting to achieve, measuring these clutches has taken away a sense of spectacle and immediacy from the final throw of each round and affected the pace and flow of premier rules matches.
With that said, we are happy to announce an amendment to this rule and an addition to our clutch design to alleviate this issue moving forward. A 1 inch wide, 1.5 inch tall vertical rectangle will be drawn inside the center of each clutch. To achieve a Premier Clutch, a player’s axe must now come to rest with the blade breaking the top and bottom of this rectangle on the surface of the target.
Best practices for drawing these stripes, recommended equipment, and stencil offerings can be found here and this information has been relayed to all IATF member organizations. This rule will go into effect officially at the beginning of the 2022-2023 Season in March, however, clubs may institute these changes early for their Premier Leagues competing this year if they so wish.
PREMIER CLUTCH ADJUSTMENT
We are happy to announce an amendment to the Premier clutch rule and an addition to our clutch design to alleviate the issue of easy clutch measurements moving forward.
A 1 inch wide, 1.5 inch tall vertical rectangle will be drawn inside the center of each clutch. To achieve a Premier Clutch, a player’s axe must come to rest with the blade breaking the top and bottom plane of this rectangle on the surface of the target.
While this rule will come into effect as of the beginning of the 2022-2023 IATF League Year in early March, 2022, clubs are welcome to implement it earlier for their 2022 Premier Leagues.
CLUTCH BOX MEASUREMENTS DIAGRAM
HOW TOS AND BEST PRACTICES
First, while venues are welcome to create their own stencils in the interim, it’s important to note that we will be partnering with Warriors Axe Throwing to provide updated stencils for purchase prior to our March kick-off date. These stencils will be available through both IATF.com and the Warriors shop and are available to ship worldwide.
- To Draw the Clutch Box
- Employ either your own, hand-made stencil or one purchased directly from the IATF or Warriors (stencils being the fastest and most accurate way to draw the clutch box on the fly).
- Use white (or light colored), oil-based paint markers instead of standard acrylic (oil based paints show up more clearly on painted clutches and won’t run).
- Place the stencil firmly on a dry clutch so that it won’t shift while painting (do not attempt to draw a clutch box on a wet or damp clutch, whether from being recently painted or recently sprayed with water).
- Solidly trace the edges of the stencil with the marker before filling in the center (do not squeeze too much paint from the marker nib when tracing the edges as that paint may bleed underneath the stencil).
- Remove the stencil and check your work (should a minor divot or bend be present, use either the clutch box marker or the clutch marker to touch up these issues).
- Adjudicating New Premier Clutches
- Gauge whether the axe blade has ‘broken’ (ie; is protruding above and below) both the top and bottom horizontal planes of the clutch box as observed from the surface of the target (see diagram above with the planes marked ‘a.’ and ‘b.’)
- If the axe has broken both these planes, this clutch attempt succeeds and the player scores 7 points.
- If the axe has broken one plane but fallen short of the other, this clutch attempt fails and the player scores 0 points for that throw.
- If the axe has broken neither plane, this clutch attempt fails and the player scores 0 points for that throw.
- League staff or match officials are encouraged to use phone camera zooms or flashlights to provide clarity if a clutch is difficult to judge.
- If the axe has landed to the left or right of the clutch box and seems to run parallel to the edge of the box but players are unsure if the axe has broken either plane, league staff or match officials may remove the axe to ascertain if the axe has ‘folded in’ white from clutch box itself.
- If white paint is visible in the cut the axe made as the staff or official is removing the axe at both the top and bottom plane of the box, this clutch is successful and the player scores 7 points.
- If there is no white paint visible or only white paint visible at either the top or the bottom plan of the box (but not both planes) this clutch attempt fails and the player scores 0 points.
FAQs
What prompted the change?
We spent the months following our announcement of the official rulebook changes in April, 2021 compiling data from Axescores, speaking to venue operators, and listening to our community of throwers. While the majority of the original rule changes we implemented accomplished the goals we prioritized last year, this specific rule had both pros and cons which we felt necessitated revisiting.
What were some of the reasons behind the original clutch rule change?
A majority of players and member organizations polled prior to the change agreed that any advanced ruleset needed to be more difficult in all facets of the game, not just for regular throws but also for clutch attempts.
With that in mind, we wanted to introduce a rule that wouldn’t require venues to have multiple clutch designs (ie; not a separate target design for Standard and one for Premier), that would be robust enough to withstand several rounds of competition (ie; not a tiny or intricate clutch that could be destroyed immediately after a few throws), and require a high level of skill to achieve (ie; difficult enough to inject excitement and uncertainty into the final throw of a round while not instantaneously becoming easy for the community after a few months of practice).
Why is this better than the original rule?
While the original Premier clutch rule accomplished the goals outlined above there were still some minor issues in this mechanic uncovered over the past few seasons, those being;
a) the lack of a visible marker to aim for when attempting a Premier clutch,
b) the loss of an instant, visual indicator of success, and
c) the necessity for time consuming measurements during the most high stakes portion of the game.
While individually these issues were small, together they were contributing factors for us to decide to make this new adjustment. We believe this new rule change addresses all of these concerns in a simple and concise fashion which also does not require a complicated management process to implement.
Looking at the dimensions of the box, does that make it harder or easier than the original Premier clutch rule?
When designing a scoring feature like the Premier scoring box, we look at scorable area. Based on a direct comparison of the original proposed Premier clutch (ie; the “1.75 inches of blade” rule), this new feature has an almost equitable amount of scorable area. Therefore neither game mechanic is easier or harder, one is simply clearer and less time consuming.
- If the axe has landed to the left or right of the clutch box and seems to run parallel to the edge of the box but players are unsure if the axe has broken either plane, league staff or match officials may remove the axe to ascertain if the axe has ‘folded in’ white from clutch box itself.
- If white paint is visible in the cut the axe made as the staff or official is removing the axe at both the top and bottom plane of the box, this clutch is successful and the player scores 7 points.
- If there is no white paint visible or only white paint visible at either the top or the bottom plan of the box (but not both planes) this clutch attempt fails and the player scores 0 points.
FAQs
What prompted the change?
We spent the months following our announcement of the official rulebook changes in April, 2021 compiling data from Axescores, speaking to venue operators, and listening to our community of throwers. While the majority of the original rule changes we implemented accomplished the goals we prioritized last year, this specific rule had both pros and cons which we felt necessitated revisiting.
What were some of the reasons behind the original clutch rule change?
A majority of players and member organizations polled prior to the change agreed that any advanced ruleset needed to be more difficult in all facets of the game, not just for regular throws but also for clutch attempts.
With that in mind, we wanted to introduce a rule that wouldn’t require venues to have multiple clutch designs (ie; not a separate target design for Standard and one for Premier), that would be robust enough to withstand several rounds of competition (ie; not a tiny or intricate clutch that could be destroyed immediately after a few throws), and require a high level of skill to achieve (ie; difficult enough to inject excitement and uncertainty into the final throw of a round while not instantaneously becoming easy for the community after a few months of practice).
Why is this better than the original rule?
While the original Premier clutch rule accomplished the goals outlined above there were still some minor issues in this mechanic uncovered over the past few seasons, those being;
a) the lack of a visible marker to aim for when attempting a Premier clutch,
b) the loss of an instant, visual indicator of success, and
c) the necessity for time consuming measurements during the most high stakes portion of the game.
While individually these issues were small, together they were contributing factors for us to decide to make this new adjustment. We believe this new rule change addresses all of these concerns in a simple and concise fashion which also does not require a complicated management process to implement.
Looking at the dimensions of the box, does that make it harder or easier than the original Premier clutch rule?
When designing a scoring feature like the Premier scoring box, we look at scorable area. Based on a direct comparison of the original proposed Premier clutch (ie; the “1.75 inches of blade” rule), this new feature has an almost equitable amount of scorable area. Therefore neither game mechanic is easier or harder, one is simply clearer and less time consuming.
Hello all,
With the new year comes change to the IATF; our Director, Heidi Rich, is stepping down from her role to take on an exciting opportunity outside of our organization. We wish her the best in her new endeavor and want to express our appreciation for her guidance and support over the past two years.
Our Commissioner, Matt Wilson, will be taking on the additional role of Interim Director over the next few months to guide the IATF into the new year.
With that in mind, Ian, Matt and Chris are working hard on some new and exciting developments. So keep your eyes and ears peeled for some exciting announcements coming this Winter and Spring. Stay tuned to our social channels for news and updates!
The IATF is happy to announce several key dates in 2022 for the Road to the IATC and the long-awaited culmination of the 2020-2021 season.
This season will officially end on March 11th, 2022, paving the way for successive IATF seasons to run from early March to early March each year, with the IATC held in Toronto moving to June, a welcome change from our traditional, cold February tournament.
The IATF will also be adjusting certain regional borders to better reflect our league populations. More importantly, we will be redrawing these regions for this season to minimize travel across borders in certain areas and to support league members wishing to travel for regional competitions by limiting additional costs for COVID testing, etc.
A map of the newly drawn Regions for the 2020-2021 Season can be found below.
On February 27th, 2022 the IATF will be partnering with 9 of our member organizations to host Regional competitions for any league participants who took part in sanctioned league play in either a Standard or Premier league during the 2020 or 2021 seasons, even partial seasons or seasons at clubs that have since closed. Regional winners are automatically entered into Round 1 of the IATC.
Regional hosts for the 2020-2021 Season are:
West: True North, Red Deer, AB
Southwest: LA Ax, Los Angeles, CA
South: Urban Axes, Austin, TX
Central: Detroit Axe, Detroit, MI
East: Ace Axe, Pittsburgh, PA
Southeast: BATL LoSo, Charlotte, NC
Northeast: BATL Portlands, Toronto, ON
Pacific: Maniax CBD, Melbourne, VIC
European: Skeeters, London, UK
Registration information will be available in the new year so stay tuned.
The weekend of March 18th, 19th and 20th, 2022 IATF members who have hosted a sanctioned Standard or Premier league during the 2020-2021 Season may choose to host a Wild Card tournament (Premier Rules.) This tournament is open to any player who has participated in a sanctioned league in either stream (Premier or Standard) but has not qualified for Round 1 of the 2022 IATC at that point in time (see qualification path here.) Look for announcements from your local club closer to the date for details.
Round 1 of the 2022 IATC will be hosted on April 8th, 9th, and 10th at all participating IATF member locations who held sanctioned leagues in either stream (Premier or Standard) from January 2020 until March 11th, 2022. The full list of those eligible for participation in Round 1 will be available shortly after completion of the 2020-2021 league year in March once we collect the data from each sanctioned league.
Should a location have closed in the interim, their players will be allowed to compete for that club’s vacant spot(s) at their nearest IATF location.
We are as excited as all of you to reach the end of this COVID extended season and we are counting the days until we kick off this year’s International Axe Throwing Championship with Round 1 at your home venues in April 2022. We cannot wait to see you all there.
*dates may be subject to change based on evolving global COVID landscape