Averages. CMA. Greensheet. Rolling.

[Diamonds85]

A question that's surely been asked a million times on here before.

But can someone explain to me how the hell they work and what the difference is between CMA, Greensheet and Rolling and why there has to be three different types of averages!! How are they even calculated (Points/Rides)*4??

Or point me to a webpage where I can find this info.

Cheers

[Cast1rn]

My understanding is that it's now based on the last 20 eligible meetings (was 10 last season)

From what I've heard it's the number of points scored/number of rides X 4.

Now if it is that simple it is beyond stupid because that can be manipulated in a very very simple manner.

It seems to be a closely guarded secret and I would love to here the equation they actually use.

[RoundTheBoards]

The NDL uses "straight averages" so they basically use all matches in the current season.

The Premiership and Championship use "rolling averages" which are based on a set number of meetings.  Once a rider has done that number of meetings, all subsequent meetings are added and the oldest matches drop off to keep it at that number of meetings.    They do tend to change the number of meetings it is based on from season to season., but I think it's in the rulebook.  (can't remember without checking)

 

Edited June 24, 2023 by RoundTheBoards

[Cast1rn]

1 hour ago, RoundTheBoards said:

    They do tend to change the number of meetings it is based on from season to season., but I think it's in the rulebook.  (can't remember without checking)

 

Unfortunately the rule book on CMA's is extremely vague, something along the lines of "riders averages will be calculated based on points scored and all eligible heats." 

 

[RoundTheBoards]

11 minutes ago, Cast1rn said:

Unfortunately the rule book on CMA's is extremely vague,

Yes I've checked the rule book.   It says calculated over "a specific number of applicable meetings".  But doesn't say what that specific number is.

However this year in the Premiership it's definitely 20 meetings, and I'm pretty sure it's 20 in the Championship too.   

So it's just the last 20 matches.   Once a rider reaches 21 matches you add the most recent one on and drop the oldest one off, to remain over 20 matches.

 

 

[Diamonds85]

1 hour ago, RoundTheBoards said:

Yes I've checked the rule book.   It says calculated over "a specific number of applicable meetings".  But doesn't say what that specific number is.

However this year in the Premiership it's definitely 20 meetings, and I'm pretty sure it's 20 in the Championship too.   

So it's just the last 20 matches.   Once a rider reaches 21 matches you add the most recent one on and drop the oldest one off, to remain over 20 matches.

 

 

That feels like a very annoying way to calculate it... Particularly if you're wanting to keep track of it by a spreadsheet... Do the people who make the rules just make it as difficult as possible for the people who keep track of these things or what!

[Gambo]

6 hours ago, Diamonds85 said:

That feels like a very annoying way to calculate it... Particularly if you're wanting to keep track of it by a spreadsheet... Do the people who make the rules just make it as difficult as possible for the people who keep track of these things or what!

It's quite easy to keep track of it via a Spreadsheet.... trust me!

You can even get a copy of a similar Spreadsheet to the one the BSPA use from www.kandysoft.com.

Edited June 25, 2023 by Gambo

[Cast1rn]

6 hours ago, Diamonds85 said:

That feels like a very annoying way to calculate it... Particularly if you're wanting to keep track of it by a spreadsheet... Do the people who make the rules just make it as difficult as possible for the people who keep track of these things or what!

My personal opinion is the more meetings that are included the better and the less influence can be had to manipulate riding positions and averages.

[RoundTheBoards]

6 hours ago, Diamonds85 said:

That feels like a very annoying way to calculate it... Particularly if you're wanting to keep track of it by a spreadsheet... Do the people who make the rules just make it as difficult as possible for the people who keep track of these things or what!

It's not difficult at all.  Quite simple to plug number of races and points scored into a spreadsheet.   It's only 3 little numbers per rider each match  (2 really since you don't have to bother with BP).  If you can't do your own simple spreadsheet, you can buy one off Kandysoft.  Better still just read the averages off the BSPA website where they're all calculated for you anyway!

How do you go on with football?  How do you calculate the percentage of possession, shots on/off target, percentage of tackles won?  Or do you just read it off OPTA?  What about Duckworth-Lewis in Cricket?      Speedway is simple!

 

[arnieg]

Or just go to gbspeedway.com

 

[Bald Bloke]

17 hours ago, Diamonds85 said:

A question that's surely been asked a million times on here before.

But can someone explain to me how the hell they work and what the difference is between CMA, Greensheet and Rolling and why there has to be three different types of averages!! How are they even calculated (Points/Rides)*4??

Or point me to a webpage where I can find this info.

Cheers

I use this, when working out if rider changes fit a team average.  

p23_issue_15.pdf (britishspeedway.co.uk)

Riders averages are worked on league meetings, with BP's not counting. For example   Joe Blogg's has scored 46 points from 22 rides, You divide the points by the rides, then x the answer by 4... 

46 divided by 22 = 2.09 x 4 = 8.36

 

[Cast1rn]

10 minutes ago, Bald Bloke said:

I use this, when working out if rider changes fit a team average.  

p23_issue_15.pdf (britishspeedway.co.uk)

Riders averages are worked on league meetings, with BP's not counting. For example   Joe Blogg's has scored 46 points from 22 rides, You divide the points by the rides, then x the answer by 4... 

46 divided by 22 = 2.09 x 4 = 8.36

 

I was hoping someone would pull that equation out, because if that's what they are using, they need to employee somebody with a GCSE in Maths to show them how wrong it is.

You have a number 6 you want moved into the main body of the team. You follow these simple steps.

Only let them take 3 rides 

Heats 2 and 14 (where they'll be up against the opposition's #7)

Reserve switch in heat 8 and boom you have 3 goes to score 3/4 points Vs the oppositions weakest rider.

3/3 X 4 = 4 

4/3 X 4 = 5.3 

You wanna know the even funnier thing put your second string through the tapes and that counts to their average too.and they'll be all set for a spot at 6 before you know it.

[Normski]

20 minutes ago, Bald Bloke said:

I use this, when working out if rider changes fit a team average.  

p23_issue_15.pdf (britishspeedway.co.uk)

Riders averages are worked on league meetings, with BP's not counting. For example   Joe Blogg's has scored 46 points from 22 rides, You divide the points by the rides, then x the answer by 4... 

46 divided by 22 = 2.09 x 4 = 8.36

 

i am sure at one time averages were just for programmed rides where now it seems to be every ride.

[dontforgetthefueltapsbruv]

2 hours ago, Cast1rn said:

My personal opinion is the more meetings that are included the better and the less influence can be had to manipulate riding positions and averages.

The argument for the numbers used is that it covers around a season 

Double the number and by July 2023 you could be using meetings ridden in 2021 - hardly a good reflection of current form

Either way can have issues - add in those starting on assessed average gaining a first real figure after just 3 home and 3 away and there will always be 'opportunities' for those looking to manipulate 

[arnieg]

1 hour ago, Cast1rn said:

I was hoping someone would pull that equation out, because if that's what they are using, they need to employee somebody with a GCSE in Maths to show them how wrong it is.

You have a number 6 you want moved into the main body of the team. You follow these simple steps.

Only let them take 3 rides 

Heats 2 and 14 (where they'll be up against the opposition's #7)

Reserve switch in heat 8 and boom you have 3 goes to score 3/4 points Vs the oppositions weakest rider.

3/3 X 4 = 4 

4/3 X 4 = 5.3 

You wanna know the even funnier thing put your second string through the tapes and that counts to their average too.and they'll be all set for a spot at 6 before you know it.

You appear to be suggesting giving your weaker reserve three rides and your strongest reserve five - not sure about that as  strategy.

I agree there are circumstances where encouraging a rider to break the tapes could be helpful in lowering averages.

I guess you'd like the system the Poles used to use where they simply ignored the reserve race in calculating averages.

[Cast1rn]

26 minutes ago, arnieg said:

You appear to be suggesting giving your weaker reserve three rides and your strongest reserve five - not sure about that as  strategy.

*Edit sorry miss read you statement**

Of course it is a solid strategy if your goal is to get your number 6 into the main body (#2)

Your number 7's average is irrelevant.

I just want someone to say "100% of course we're not using"

number of points/number of rides X 4

Because if you are, the minute you take 3 rides your average will be inflated.

 

Edited June 25, 2023 by Cast1rn

[arnieg]

1 hour ago, Cast1rn said:

Because if you are, the minute you take 3 rides your average will be inflated.

Not necessarily, it depends which heats you take those rides in.

[Cast1rn]

1 hour ago, arnieg said:

Not necessarily, it depends which heats you take those rides in.

100% it does.

The average of something is the number of points divided by the number of attempts. If you only make 3 attempts at something and we use a multiple of 4 then of course the calculated average would be greater than what you actually score.

If I rode 3 times in 16 home/away  meetings and scored 3 points every single time then even the most mathematically challenged person could tell me that my average was 3. 

However using the wonders of equation creation 3/3 x4 (or 48/48 X4,) would give me an average score of 4. Never mind the fact that I have never ever ever scored 4 points in any of those 16 meetings.

So back to the original point if a rider only rides in 3 rides then his or her average for that match would be inflated unless...... Wait for it ...... They scored 0 from 3 rides.

But again this is all hypothetical as there is no way something so simple could be used to determine riders averages.

 

Edited June 25, 2023 by Cast1rn

[Diamonds85]

6 hours ago, RoundTheBoards said:

It's not difficult at all.  Quite simple to plug number of races and points scored into a spreadsheet.   It's only 3 little numbers per rider each match  (2 really since you don't have to bother with BP).  If you can't do your own simple spreadsheet, you can buy one off Kandysoft.  Better still just read the averages off the BSPA website where they're all calculated for you anyway!

How do you go on with football?  How do you calculate the percentage of possession, shots on/off target, percentage of tackles won?  Or do you just read it off OPTA?  What about Duckworth-Lewis in Cricket?      Speedway is simple!

 

I can very easily knock up my own spreadsheet... But it would be difficult to include a calculation that would include the last 10 results only, without having to redo the calculation for every meeting, or deleting the 1st meeting of the 10 included, as far as my excel skills go anyway, I dunno if it's possible to calculate only the last 10 figures entered into a table or something?

[arnieg]

2 minutes ago, Cast1rn said:

100% it does.

The average of something is the number of points divided by the number of attempts. If you only make 3 attempts at something and we use a multiple of 4 then of course the calculated average would be greater than what you actually score.

If I rode 3 times in 16 home/away  meetings and scored 3 points every single time then even the most mathematically challenged person could tell me that my average was 3. 

However using the wonders of equation creation 3/3 x4 would give me an average score of 4. Never mind the fact that I have never ever ever scored 4 points in any of those ten meetings.

So back to the original point if a rider only rides in 3 rides then his or her average for that match would be inflated unless...... Wait for it ...... They scored 0 from 3 rides.

But again this is all hypothetical as there is no way something so simple could be used to determine riders averages.

 

Firstly the CMA is 4 as the point of the calculation is to normalise for the number of rides taken, and secondly if you are going to suggest I am mathematically challenged you really should be aware that I have a degree in Maths.