Not able to use SWU on Premium Economy?
#31
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Join Date: Oct 2011
Location: LAX
Programs: AAdvantage EXPLAT, Hilton Diamond, SPG/Marriott Gold, IHG Platinum, Citi Exec MC, Amex Plat
Posts: 1,443
Yup, I will probably only hit PLT next year with pretty much all my qualifying activity in Jan-Feb 2019, and then likely a long hibernation until mid-2020 when I may pick up some trips again. So, virtually after Feb 2020, I'd be at 0 rolling EQDs.
#32
Join Date: Jul 2003
Location: Gatwick, UK
Programs: UA *G, BA Silver
Posts: 1,669
The birthday paradox means that the odds of a collision are a lot higher than you initially think. If PLTs were evenly distributed across say 5000 EQDs values, it would only take 84 of them on the same flight for there to be a 50/50 chance of two of them having the same EQD value. On the other hand, if there were only 20 PLTs on each upgrade list, you'd only have a 6% chance of a collision so you'd only expect to see one every 16 or 17 flights, but it would definitely still happen from time to time (but would be the exception rather than the rule.
The birthday paradox is about two random people sharing a birthday - if I'm interested in the number sharing my birthday the probabilities are much smaller. But in the upgrade scenario we are talking of the person next to me sharing my birthday, which is very very small.
#33
Join Date: Jun 2001
Location: New York, NY
Posts: 3,698
Given that there are only (say) 5 upgrades available for any flight it doesn't matter if there are 84 PLTs on the upgrade list or 10. The tiebreaker only matters if two of the first 5 on the list have a matching EQD value. Or rather the tie breaker only matters between the 5th and 6th on the list. So the probability of EQD failing to resolve the upgrades is really really small. Thus, the probability of any two PLTs on a flight having the same EQD is maybe surprisingly high, but the probability of it being relevant to upgrades is surprisingly small.
The birthday paradox is about two random people sharing a birthday - if I'm interested in the number sharing my birthday the probabilities are much smaller. But in the upgrade scenario we are talking of the person next to me sharing my birthday, which is very very small.
The birthday paradox is about two random people sharing a birthday - if I'm interested in the number sharing my birthday the probabilities are much smaller. But in the upgrade scenario we are talking of the person next to me sharing my birthday, which is very very small.
#34
Join Date: Jul 2003
Location: Gatwick, UK
Programs: UA *G, BA Silver
Posts: 1,669
In fact, the only comparison that really matters is whether two people at the border between "upgraded" and "not upgraded" have the same number of EQDs, because it doesn't really matter if #1 and #2 on the list have the same EQDs if there's five upgrades available--the key would be breaking a tie between #5 and #6 . If we go back to the (almost certainly incorrect) assumption that PLTs are distributed evenly across 5000 EQD values, then the odds that the two people right at the boundary line have the same EQDs are only 1 in 5000. That's obviously quite uncommon, but still means that it would happen on average every day somewhere across the system.
One fascinating wrinkle arises from the fact the status derives from a calendar year EQD value (which must be greater than a minimum value, but has no maximum value) whereas the EQD tie-breaker derives from a rolling 12-month value (which has no fixed minimum value or maximum value). Furthermore on Jan 1 these two EQD values are pretty much equivalent, but on Dec 31 they could be wildly divergent. Two things follow:-
- one cannot know how many EQD values PLTs are distributed across
- the distribution of PLT EQD values grows larger steadily as the calendar year rolls on
It really would be fascinating to try and model this mathematically, but I think that is beyond me.
#35
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Join Date: Jan 2002
Posts: 44,420
One fascinating wrinkle arises from the fact the status derives from a calendar year EQD value (which must be greater than a minimum value, but has no maximum value) whereas the EQD tie-breaker derives from a rolling 12-month value (which has no fixed minimum value or maximum value). Furthermore on Jan 1 these two EQD values are pretty much equivalent, but on Dec 31 they could be wildly divergent. Two things follow:-.
On Jan 1 , the current year EQDs towards retaining/attaining status will be zero , but the 12 month rolling period will cover all ( or from Jan 2 ) of the previous year
On Dec 31, the current year EQDs towards retaining/attaining status will be the same as the 12 month rolling period ( or almost the same if Dec 31 of previous year is also counted )
#36
Join Date: Apr 2009
Location: YYF/YLW
Programs: AA, DL, AS, VA, WS Silver
Posts: 5,950
Certainly seems plausible enough that it makes sense for AA to list a tiebreaker after EQDs. But not probable enough at all to justify a statement that premium economy trumps economy in the SWU upgrade order, especially for a customer who has non-zero last-12 months EQDs, the motivation for this digression.
#37
Join Date: Jul 2003
Location: Gatwick, UK
Programs: UA *G, BA Silver
Posts: 1,669
I am not sure why they would be equal on Jan 1 and divergent on Dec 31
On Jan 1 , the current year EQDs towards retaining/attaining status will be zero , but the 12 month rolling period will cover all ( or from Jan 2 ) of the previous year
On Dec 31, the current year EQDs towards retaining/attaining status will be the same as the 12 month rolling period ( or almost the same if Dec 31 of previous year is also counted )
On Jan 1 , the current year EQDs towards retaining/attaining status will be zero , but the 12 month rolling period will cover all ( or from Jan 2 ) of the previous year
On Dec 31, the current year EQDs towards retaining/attaining status will be the same as the 12 month rolling period ( or almost the same if Dec 31 of previous year is also counted )
But actually, current year EQDs do play into it in some way since status can also be determined by those (one can go up but not down in status during the year). Of course, the month of January is a further anomaly since status then can be determined by either of the two previous calendar years.
But in general the key point is that the range of values for the 12-month rolling EQDs for PLTs can be from 0 to somewhere pretty high (15000 or even 16000 probably), and certainly not evenly distributed over that range.
[I think I'm reasoning correctly through here - as a former applied statistician - but with these kinds of real-world applied maths problems it is very easy to be led astray.]
#38
A FlyerTalk Posting Legend
Join Date: Jan 2002
Posts: 44,420
What you say is correct, but it is not actually relevant current year EQDs do not play into either the upgrade process or my current status. What I was saying would be equal on Jan 1 are the last calendar year's EQDs (that determined your status) and your rolling 12-month EQDs (that determine upgrade tiebreaks).
On 31 December , that is the one time when all is based on what has happened that year. At any other point in the year, the current year's activities may be more or less relevant
#39
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Join Date: Oct 2011
Location: LAX
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Yeah, that scenario and lifetime Platinums/Golds who havent flown paid tickets in the last year would also have zero EQDs. Id think zero is the most likely tie value in the EQD category. And since even Golds do sometimes get upgraded, the fare class category probably does occasionally come into play when getting to the bottom of the Platinum part of the upgrade list.
Certainly seems plausible enough that it makes sense for AA to list a tiebreaker after EQDs. But not probable enough at all to justify a statement that premium economy trumps economy in the SWU upgrade order, especially for a customer who has non-zero last-12 months EQDs, the motivation for this digression.
Not that hard to fathom as it's possible to hit EXP with just a handful of segments.
#40
Join Date: Jul 2003
Location: Gatwick, UK
Programs: UA *G, BA Silver
Posts: 1,669
Even an EXP can also have 0 EQDs if they had to take some big trips early this year, and then hibernate till mid next year, then at that point, their rolling EQDs go to 0 while still holding EXP status.
Not that hard to fathom as it's possible to hit EXP with just a handful of segments.
Not that hard to fathom as it's possible to hit EXP with just a handful of segments.
But this is all a digression. The laws of probability mean that there will be occasions where a tie-breaker is needed after EQDs. Attempts to estimate the probability of that though will founder on the fact that there are no straightforward ways to estimate the distribution of EQD scores for any given status group.
#41
Join Date: Jul 2001
Programs: AA EP
Posts: 2,203
#44
Join Date: Jan 2012
Programs: AA EP; HH Diamond; Marriott Plat; IHG Plat; National EE
Posts: 342
No EXP upgrades from Y to PE for transatlantic flights?
Is it correct that the same-day EXP upgrades from Y to PE that initially were offered on transatlantic flights last year are no longer offered? Flying award ticket next spring to LHR.
Assuming the answer is yes, any experience with whether paid Y to PE "upgrades" are offered online or at the airport kiosk same day?
Assuming the answer is yes, any experience with whether paid Y to PE "upgrades" are offered online or at the airport kiosk same day?
#45
Join Date: May 2011
Location: DFW
Programs: AA EXP, LT Gold
Posts: 3,143
Now, the language on the website only seems to make domestic PE upgrades complimentary to EXP/CK's... which is basically just to Hawaii.
Someone - in this thread, or another - reported they have been able to sweet talk the AC agents into upgrading him complimentary to PE on INTL flights once he got to the lounge before departure.
Other than that, you can request a cash upgrade at check-in. I think reports have been from $350-$450.