THE FISO GUIDE TO FPL PLAYER PRICE CHANGES

This season's Price Change Site can be found HERE. It is now active.

PLEASE NOTE:
! This site is updated every day at 09:00, 13:00, 17:00, 20:00, 21:00, 22:00.

! FPL.com price changes occur between 00:30 and 03:30 each day.

!Note! Price changes for players with less than 1% ownership (see FPL site) can not be deduced and are not included.

! The rise and the fall thresholds will vary over the season. Any changes to this algorithm will be reflected on diamondplus's site at his earliest opportunity. For this reason users must accept the possibility of inaccuracies on the site.

! There is a margin of error of 1% implicit in all 'Price Drops: Selected By' statistics due to the limited details FPL.com give managers. This small margin of error can sometimes result in prices not falling when predicted by the site.


We are indebted to forum member diamondplus for this information.

IMPORTANT!
1) FPL.com's algorithms are secret and may take some time to determine. Please bear with the FISO Boffins during the refining process.
2) This information is used at your own risk.
diamondplus maintains this website in his spare time and for no financial reward. While he will endeavour to keep it up to date this is not always immediately possible and he is under no obligation to do so at all. Users must take responsibility for their own actions. FISO and diamondplus accept no responsibility for errors on the site, nor for the actions of those using the site as a guide to price changes.

IMPORTANT NOTES

Price Rises:
Player price rises occur when a set number of Net Transfers In (NTI) have occurred.
The NTI is determined from 'Transfers In - Transfers Out', as given on FPL's Stats.

The NTI at which a player's price is increased by 0.1m is known here as 'the NTI Threshold'.
The NTI Threshold is decided by FPL themselves and has varied during past seasons, starting around 20,000 to 21,000 NTI and decreasing as the season progresses.
(Solely for the purposes of this explanation only I shall assume an NTI Threshold of 17,000. This figure is based on previous season's data. The true figure is currently: Circa 20K NTI (26/9/08) )

Price Falls:
Price falls of 0.1m occur when a player's NTO (NTO = Transfers Out - Transfers In) reaches a particular number. We call this number the 'Fall Threshold'. A player's Fall Threshold is determined by a fall of X% of a player's ownership in the transfer market, where 'X' is a number decided upon by FPL.com.
That number is currently circa 9.5%. For ease of explanation, I shall use 10%.

A player's Fall Threshold is determined by FPL as follows:
If 10% of managers owning a player sell him his price falls by 0.1m.
(Solely for the purposes of this explanation only I shall assume the FPL's chosen % is 10%, as the true figure is both not known at the time of writing and variable. This figure is based on previous season's data.)

But how many is 10% of his total managers?
To establish this figure, first find the '% of Managers Owned By' stat from that player's (i) profile.
Then find the 'Total Players' stat (on My Team page and others).
Divide that by 100, then multiply the result by the % he is owned by.
This gives the total number of managers who own him.
Next, divide that figure by 10 to establish what '10% of Managers who own him' is.
This figure is his NTO Fall Threshold. When this number of net transfers out occurs his price will fall by 0.1m.


Price drops for players whose price is above their initial value

A player whose price is above their initial value may still follow the rules above when it comes to dropping if his ownership is low enough. However players where the absolute value of the 10% threshold will be greater than the NTI threshold will fall at the negative NTI threshold.


Note:
1) Players' prices will only rise or fall by a maximum of 0.1m per day.

2) NTIs and NTOs in excess of any threshold are not carried over towards the next price change when that threshold is passed, but are 'lost to the economy'. After any price change the counter is reset to zero and a new count commences.

3) Any second rise or fall that gameweek will require two times the original number of NTIs or NTOs, respectively.

4) Any third rise or fall that gameweek will require three times the original number of NTIs or NTOs, respectively.

5) At the end of any given gameweek the thresholds return to their basic level.

Consequently, any player who has risen in price once that week (getting circa 17K NTI) and finds himself somewhere between the First Rise Threshold and the Second (getting yet another (circa) 17K - 33K NTI) on Friday (or the last day of that gameweek) is guaranteed to rise on the first update of the new gameweek when the NTI Threshold returns to 17K.


Flagged Players:

1. Injured, doubtful, ineligible and suspended players will continue to rise or fall. The rise threshold remains as normal, but the fall threshold is increased to around 22.5%. Players with a prior price increase will fall at the 22.5% threshold OR 2.5 x negative rise threshold, whichever is lower (see rule 5 above).

2. When a player returns to fitness/eligibility (grey "i") the following conditions apply:

Only having been red flagged for one day, or yellow flagged: Reset to 0 and count begins immediately

Red flagged for more than one day: Transfers will not count for seven days, the price will not change during this limbo period. After 7 days the count is reset to 0 and transfers have their normal effect.



Transferred Players:

Players transferred in or out will be exempt from price changes for seven days. Their price will not change during this limbo period. After 7 days transfers have their normal effect with the count starting at 0.

Thread History

The original 'Code Thread' can be found here: Cracking the Code - A FISO Guide to Determining Price Change'.
'Page 1, Post 1' contains a summary of how the FPL.com price fluctuations were determined in the 2006/07 season.

The 'Roll of Honour', acknowledging the contributions of those members involved in this endeavour, can be found here.

At the start of the 06/07 season members of FISO set out to determine how player price changes were decided in the FPL.com game.

Despite the limitations of the information available to us we succeeded - near as dammit, anyway!

What started as a manual effort was, throughout the season, refined by the membership. Our IT experts were eventually able to provide all the information we require, available at the click of a button!

The pinnacle of this group achievement came when diamondplus automated the stats-gathering process and provided a webspace available to us all!

The 2007/2008 Price Change Thread built on the previous season's successes and can be found here.

I think there is something wrong with the website... it claims De Ridder costs £9m and rising:)

and Rosenior is a Fulham player too

And cudicini is close to a rise in price!!!

I wouldn't trust anything on dp's site until he tells us he's satisfied it's up and running properly.

Obviously a mixup with the reference to the database (somehow...?)

But its relatively easy to figure out who the players actually are, by their prices and how close they are to increasing relative to their net transfers in on the FPL site.

Obviously its not exactly running properly, but off the top of my head, I'm guessing:

6.5 mil , Mido = Ashton
5 mil, Parker = Geovanni
7.5 mil, Cudicini = Arteta (maybe Nasri?)
9 mil , De Ridder = Santa cruz
5 mil , Clichy = Djourou
5 mil , Van Der Sar = Wheater
4.5 mil , Samba = O'Brien, J ?
12 mil , Rosenior = Torres

You may be right, desi_jockey.
However, until we see a price rise or 12 we won't know what the Threshold level is at the start of this season (as they change through the year).

Fortunately, during the first week it's easy to see who the big movers are by looking at the Transfers IN/ Out stats on FPL, so hopefully no one should get caught out before the site starts operating properly.

What was the threshold last year, as I remember it being around 15,000.

Nasri and Geovanni are already over 10,000 and Arteta's pushing on at 9,000, they may even rise tonight

Sorry to sound stupid, but where do I find this data please? Thanks in advance...

Go to FPL -> Fantasy Stats -> Choose 'Select Filter' for GK/Def/Mid/For, then 'Select Statistic'.
Towards the bottom of the options you'll see Transfers In and Transfers Out for the Gameweek and the Season (the same right now, of course).

To establish the NTI, take the TI and subtract any TO.
Similarly for NTOs.

Many thanks!

Well over 12,000 now. Deco's at 9000 on the back of today

Possible, but it's been early Tuesday am BST before any changes for the past two years

FPL Transfer Situation @ 17th August 2008 23:50

Transfers In

Goalkeepers »
Cech CH 6 3582
Reina LI 6 1816

Defenders »
Djourou AR 5 7623
Bosingwa CH 6 5029
Wheater MI 5 4774
Cahill BW 4.5 2532
Gallas AR 6.5 1600
Ricketts HU 4 1549

Midfielders »
Geovanni HU 5 13051
Nasri AR 7.5 12593
Arteta EV 7.5 11436
Deco CH 9 10293
O'Brien J BW 4.5 3713
Alonso LI 6 2151
Lampard CH 11 1805
Cole J CH 9 1598
Nolan BW 6 1491
Dunn BR 6 1446

Forwards »
Ashton WH 6.5 10399
Agbonlahor AV 8 9509
Santa Cruz BR 9 6461
Torres LI 12 2695
Anelka CH 9.5 1735
Yakubu EV 8 1657
Folan HU 5 1637

Transfers Out

Goalkeepers »
James PO 6 3337

Defenders »
Lescott EV 7 2796
Johnson PO 5.5 2479

Midfielders »
Fabregas AR 10 10176
Modric TH 7.5 3774
Bentley TH 8 3667
Essien CH 8 3203
Dempsey FU 5.5 2908
Davies FU 6 2707
Petrov MC 7.5 2606
Kranjcar PO 6.5 2539
Hamann MC 4.5 2497
Ronaldo MU 14 2376
Gerrard LI 11.5 2171
Ireland MC 5.5 1829
Downing MI 7.5 1810
Mascherano LI 5.5 1769

Forwards »
Keane LI 9 3735
Berbatov TH 9.5 3704
Defoe PO 8 3230
Adebayor AR 11 2904
Tevez MU 10 2767
Van Persie AR 9.5 2456
Bent TH 7.5 2398
Kitson ST 5.5 2111

I don't want to clutter up this thread... but does anyone know how I can set this up as a web query in Excel? I just keep getting the overall points info as the URL never changes.

If I can get the info straight to Excel I'm happy to post any update to price changes at hours that are unGodly to most of you in Europe.

Ah, don't worry, I've got it now.

Some big movers in the Transfers In stakes at the moment.

Unless they've changed the formula, or the myth of a price freeze is true, Geovanni, Nasri and Deco should go up tonight!

Geovanni, Deco, Nasri, Arteta, Ashton and Agbonlahor should all go up tonight, there's an outside chance of Djourou rising and I'd be careful if you were planning on bringing in Bosingwa.

Well no one went up last night, so I guess it is definite to happen tonight.

The trouble is to pick players that you think will go up twice, presuming you are just buying for a profit...

I can't see Djourou falling into that group, considering Toure was on the bench at the weekend. The rest should all be safe enough in this regard.

although fabregas now has a total of over 15,000 NTOs, will his 'red i' prevent him from dropping in price this week? was hoping to catch him at a slightly reduced price - 9.9m feels so much better than 10.0m...!

Please read the second post.

You may well be able to pick him up later on at 9.9m. (9.8m is possible, but unlikely given his short term injury).

What's the loss threshold likely to be for an injured Fabregas? Can't even remember the basic threshold.

thanks flyman. so theres a decent chance he'll drop this week. just need to decide if i should lose adebayor to get him in

adebayor -> agbonlahor
osman -> fabregas

worth the 4 point hit? i doubt it, but dont want to be left with neither arsenal players. looks like it could be the (not-so) popular turnbull -> jones

Devious wrote:

-25%.

Sooo ...... given 130000 managers; owned by 22.4% = 291200 now.

17121 (T0) - 431 (TI) = 16690 NT0

Therefore, at the start of the game Fabs was owned by 291200 + 16690 = 307890

25% of 307890 = 76,972 NTO for 0.1m price drop.

I know it seems a lot, but I think we saw the same thing last season with Ronaldo's red card. When a popular player is red (i)'d it takes one helluva lot of transfers out to drop him
Of course, this means that mass exoduses don't tend to lower a player's price too dramatically - which is exactly what the 25% NTO threshold is designed to do.
Conversely, the '7 day price freeze' when the red (i) is removed prevents the prices rocketing as everyone piles back onto the bandwagons.
All in all, it seems to balance out very well.

No! I've just done the sums (see above) and I think it extremely unlikely that Fabs will drop this week.

Deco's near 20,000 now.

Wasn't Bosingwa flagged for a few days at least and the flag was removed just a few days ago.
So he should be protected for quite many days still?

Right now I'm new to trying to understand all this price change malarky but can someone confirm if I've got this right.

If I brought in, say, Geovanni now and his price went up tonight, I'd only be paying whatever price now, not his price at the start of the next GW?

(Sorry if it's asking the obvious but I'm not all that sure)