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General => General Technical Chat => Topic started by: Deni on February 14, 2020, 06:34:26 pm

Title: Is Ebay rigging bids?
Post by: Deni on February 14, 2020, 06:34:26 pm
I have an odd situation here. I saw an interesting instrument on e-bay and placed auto-bid with $250 as a limit.
After a while ended with highest bid but sequence of bids look very strange:
[attachimg=1]
My bids are marked red and you can see my first bid at $55 placed on 13.02.2020 at 9:26, then it was overbidded by
a bidder 6***4 (which has no previous bids on that auction!) at 5:43 but on 12.02.2020 (a day before) !!! And then my auto-bid
increased to $202,50 16 seconds after my first bid.

Perhaps I am just plain stupid or just do not know how things work so please enlighten me...
Title: Re: Is Ebay rigging bids?
Post by: tom66 on February 14, 2020, 06:39:36 pm
This happens if someone has placed a bid above your bid but as an autobid...

Say auction is at $50, but they bid $202.50.  It goes to $55 because that is the next bid-increment.  You come in at $200 and the eBay system recognises the auto bid and places the bid on the other buyer's behalf, you lose the auction.

The best way to avoid losing these auctions is a sniping service like Gixen; it avoids the auction price war that happens and you "snipe" at exactly the price you want. The autobidder ensures you pay no more than this, or the bid increment above the highest autobid.
Title: Re: Is Ebay rigging bids?
Post by: Deni on February 14, 2020, 06:45:02 pm
This happens if someone has placed a bid above your bid but as an autobid...

I understand that, but it still does not explain this situation. If bidder 6***4 placed his auto-bid for $200, he should already be top bidder before bidder 6***3
placed his bid (on 12.02. at 10:31) but he's nowhere on the list until I placed MY autobid !!! That's the part which I do not understand. How can you place an
auto bid that is NOT executed?
Title: Re: Is Ebay rigging bids?
Post by: PA0PBZ on February 14, 2020, 06:51:28 pm
I think it shows only the highest bid from the other bidders, and I remember having seen a button called something like "show all bids" which as expected then shows all bids.
Can you share the link to the item?
Title: Re: Is Ebay rigging bids?
Post by: Deni on February 14, 2020, 07:02:23 pm
Here is the full history which still does not explain it. Timeline for bidder 6***4 is simply not right. And I also recall that the last price when
I placed my first bid was $50, not $51 as suggested by this list:

[attachimg=1]
Title: Re: Is Ebay rigging bids?
Post by: PA0PBZ on February 14, 2020, 07:19:22 pm
There are still bids missing, otherwise I can't explain the 2 consecutive bids from r***r for $11 and $50, there must be a $49 bid in between. I wonder if it shows you (as one of the bidders) something else than a 3rd party but since it looks like you are not willing to share the link I can't have a look myself. Is it a sensitive item? ;) If you don't want to put it here for everyone to see you can pm me.
Title: Re: Is Ebay rigging bids?
Post by: jogri on February 14, 2020, 07:28:22 pm
There are still bids missing, otherwise I can't explain the 2 consecutive bids from r***r for $11 and $50, there must be a $49 bid in between. I wonder if it shows you (as one of the bidders) something else than a 3rd party but since it looks like you are not willing to share the link I can't have a look myself. Is it a sensitive item? ;) If you don't want to put it here for everyone to see you can pm me.

I guess person 6 bid 49 bucks when the highest bid was 11 bucks, then the autobid for person r kicked in and bid 50. Or person r just decided to up his bid.

This screenshot looks like it doesn't show every automatic bid, but you can take a look at them on ebay.
Title: Re: Is Ebay rigging bids?
Post by: Stray Electron on February 14, 2020, 08:00:03 pm
I have an odd situation here. I saw an interesting instrument on e-bay and placed auto-bid with $250 as a limit.
After a while ended with highest bid but sequence of bids look very strange:
(Attachment Link)
My bids are marked red and you can see my first bid at $55 placed on 13.02.2020 at 9:26, then it was overbidded by
a bidder 6***4 (which has no previous bids on that auction!) at 5:43 but on 12.02.2020 (a day before) !!! And then my auto-bid
increased to $202,50 16 seconds after my first bid.

Perhaps I am just plain stupid or just do not know how things work so please enlighten me...

   I agree with the other posters, there's something missing here.  For one thing, it shows 6***4 making three different bids all at exactly the same moment. Apparently it's not showing the actual time when Ebay auto-incremented his bid but it clearly did auto-increment it.

    Actually if you start at the bottom and look at the just the time sequence and not the amounts, it does look right except that when the system auto-incremented it showed the time of the bidder's original bid and not the time that it incremented.

   I don't agree with some of the other posters about needing to use a sniping service. Do as E-bay says and bid your top bid to begin with and then sit back and wait and see if you win.  A sniping service is only useful to that emotionally weak people who can't stop bidding and that take it as a personnel challenge when someone outbids them. It is hard to avoid the temptation to keep bidding, that's why I place my bid and then I don't even look at the auction again until it ends.
Title: Re: Is Ebay rigging bids?
Post by: thinkfat on February 14, 2020, 08:01:08 pm
There are still bids missing, otherwise I can't explain the 2 consecutive bids from r***r for $11 and $50, there must be a $49 bid in between. I wonder if it shows you (as one of the bidders) something else than a 3rd party but since it looks like you are not willing to share the link I can't have a look myself. Is it a sensitive item? ;) If you don't want to put it here for everyone to see you can pm me.

No, this is a completely fine bidding history. You just don't realize how the autobid mechanism works. Look at the timestamps, it is completely transparent.

The 2 consecutive bids from r***r are his first bid (autobid to $50) which is shown as $11 first, since this initial bid trumped the previous highest bidder (6***3, $10,50)
The next bid was by 6***4 (autobid to $200), which is shown as $51, because it trumped r***r's autobid to $50 (which is directly below). Note that the timestamps on all r***r bids are the same, it's the time he put in his $50.

Then you placed your bid to $55, which got immediately trumped by 6***4's autobid, raising the price to $56. See the timestamp on 6***4's bids, it's identical.

Then again you placed your final bid to $202,50, which trumped 6***4's autobid to $200 (it's listed directly below yours to maintain sequence). Note again, all timestamps on 6***4's bids are the same, he interacted just once and put $200 as his max. All other things happening were automatic doings of the Ebay system. The only one who raised their stakes in the auction was you.

It's all completely normal.

Correction, it _would_ have been completely normal if 6***4 had shown up earlier somewhere. You're right, there seems to be something missing in the bid history, an initial autobid to $200 by 6***4 should have shown up _somewhere_.
Title: Re: Is Ebay rigging bids?
Post by: sleemanj on February 14, 2020, 08:47:52 pm
Looks normal to me...
(https://i.imgur.com/5VGxid4.jpg)
Title: Re: Is Ebay rigging bids?
Post by: ebastler on February 14, 2020, 08:57:19 pm
@Deni, did you by any chance neglect to mention that you first placed a $55 bid, and then (a bit later) a $250 bid? That's what it looks like to me. Your fist bid was overbid by the one which 6***4 had made the day before, your sencond bid went higher than his.
Title: Re: Is Ebay rigging bids?
Post by: tunk on February 14, 2020, 09:17:57 pm
The times confused me at bit at first, but according to wikipedia 12:29:39PM could (should?) be read as 00:29:39PM.
Title: Re: Is Ebay rigging bids?
Post by: george.b on February 14, 2020, 09:38:43 pm
The times confused me at bit at first, but according to wikipedia 12:29:39PM could (should?) be read as 00:29:39PM.

Well, there's no such thing as 00:29 PM. 00:29 is 12:29 AM (ante meridiem, before midday). 12:29 PM (post meridiem, after midday) is 12:29 in the 24-hour format.
Title: Re: Is Ebay rigging bids?
Post by: Deni on February 14, 2020, 09:39:41 pm
[attachimg=2]
@Deni, did you by any chance neglect to mention that you first placed a $55 bid, and then (a bit later) a $250 bid? That's what it looks like to me. Your fist bid was overbid by the one which 6***4 had made the day before, your sencond bid went higher than his.

Actually, you're right. But it still does not explain everyhing - see below:

Auction ended just now and here is the final list with all bids shown (unless e-bay is not showing everything).

So there's still one thing which does not fit the picture - how can 6***4's first bid ($51) be on the 7'th position from the bottom? If he placed auto-bid for $200 on 12.02 at 5:43 it should first
appear 5'th on the list, just after 6***3's. Instead, there's r***r's bid.

Also, note that the bidder's names are some random letters - if you click on a bidder it will show stats with some other random name but number of transactions is the same.
As everything else is obfuscated, it is impossble to tell what data are actual and what are, well, not...

Please note that I do not want to post any ebay links as it will reveal my ebay name and I am not comofrtable with that.

Title: Re: Is Ebay rigging bids?
Post by: sleemanj on February 14, 2020, 09:44:00 pm
12 PM on the 12th of February is before 5 PM on the 12th of February

The order is correct.  Are you confusing AM and PM?  12 AM is midnight, 12 PM is lunch time.

r***r bid at 12:29 PM, Lunchtime
6**4 bid at 5:43 PM, early evening
Title: Re: Is Ebay rigging bids?
Post by: Deni on February 14, 2020, 10:01:57 pm
Yes, it seems that there's incorrect time display. According to NIST 12AM and 12PM should not be used, since they are ambiguous :
https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs (https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs).

Sequence of bids looks like this:

r***r placed auto-bid of $50 at 12:29 (24-hour format). This outbid 6***3's bid and when reached $50 triggered 6***4's autobid (set to $200) and stopped
with 6***4's bid to $51. But when did 6***4 placed his initial bid that caused r***r's bid to hit $50? Still does not make sense or e-bay nevertheless does not
show all bids...

I was always wondering - now when everything is run automatically and you can't see your opponents, it looks like playing poker with a machine... :)
Title: Re: Is Ebay rigging bids?
Post by: sleemanj on February 14, 2020, 10:15:04 pm
It's not that complicated.

  09/02 03:11 7***l places an auto bid for $10, it sits at $9.99
  12/02 10:31 6***3 places a bid for $10.50, this maxes out the previous bidder at $10
  12/02 12:29 r***r places an auto bid for $50, it sits at $11
  12/02 17:43 6***4 places an auto bid for $200, this maxes out the previous at $50 and sits at $51
  13/02 09:26:22 you place a bid for $55, 6***4's auto increases to $56
  13/02 09:26:06 you place a bid for $202.50, this maxes out 6***4 at $200 and you now lead the bidding



Title: Re: Is Ebay rigging bids?
Post by: Deni on February 14, 2020, 10:25:59 pm
It's not that complicated.
  09/02 03:11 7***l places an auto bid for $10, it sits at $9.99
  12/02 10:31 6***3 places a bid for $10.50, this maxes out the previous bidder at $10
  12/02 12:29 r***r places an auto bid for $50, it sits at $11
  12/02 17:43 6***4 places an auto bid for $200, this maxes out the previous at $50 and sits at $51
  13/02 09:26:22 you place a bid for $55, 6***4's auto increases to $56
  13/02 09:26:06 you place a bid for $202.50, this maxes out 6***4 at $200 and you now lead the bidding

Yes, you are right -  AM/PM thing messed it up, but that's correct sequence... It would be too obvious - but now when I think of it - since e-bay charges a
percentage of sale, it's in their interest to get the highest price possible. When you enter auto-bid value, it's pretty easy to manipulate bidding process,
since you can't see actual account names (and links can point to basically anything). Say, you enter $500 as your maximum bid, algorithm can decide to
create a few fake bids and pump out more money from you than you should actually pay as long as the final amount is less or equal to $500.
You do it randomly, with various end-price differences and at various times, so there won't be visible pattern. Randomize the whole process good enough
and buyers would not  be able to spot it, sellers does not care since they will get more money for their stuff and everybody is happy... Best of all - you can't be caught !
Of course, if buyer is not using auto-bid then the whole scheme falls apart, but I guess there's a lot users using auto-bid, as you normally cant' spend the whole
day looking at e-bay.
Or I am just paranoid?
Title: Re: Is Ebay rigging bids?
Post by: nctnico on February 14, 2020, 10:30:44 pm
Looks normal to me...
(https://i.imgur.com/5VGxid4.jpg)
I agree. This looks like a normal bid history to me. It is Ebay's auto-bidder at work just like it should. The only thing is that the auto-bidder shows the bid time as the time the original bid was entered and not when the auto-bid was made.
Title: Re: Is Ebay rigging bids?
Post by: I wanted a rude username on February 14, 2020, 10:31:40 pm
12AM and 12PM should not be used, since they are ambiguous

They are unambiguous. They are just illogical to us, because we are aware of the concept of zero.

If you keep in mind that PM is post meridiem (after noon), it almost makes sense (12:00:00 is technically not after noon).

Anyway, another example of the supremacy of 24 hour time.

Or I am just paranoid?

Yes.  ;)
Title: Re: Is Ebay rigging bids?
Post by: Muttley Snickers on February 14, 2020, 10:45:11 pm
If the OP made only one bid of $250 why then do they have two time stamped bids 16 seconds apart ?, yet the opponents time stamps are all the same. I thought the autobids were always applied and stamped at the time of the initial ceiling bid.   
Title: Re: Is Ebay rigging bids?
Post by: Deni on February 14, 2020, 10:49:41 pm
I have explained that - first I placed $55 bid and then decided to place $250 auto-bid a few seconds later.
Title: Re: Is Ebay rigging bids?
Post by: Deni on February 14, 2020, 10:53:13 pm
Quote
They are unambiguous. They are just illogical to us, because we are aware of the concept of zero.

Well, NIST does think so (https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs (https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs)) - see first line after sub-title "Are noon and midnight referred to as 12 a.m. or 12 p.m.?"
And I take them as pretty good authority on the subject  ;)
Title: Re: Is Ebay rigging bids?
Post by: Muttley Snickers on February 14, 2020, 11:00:33 pm
I have an odd situation here. I saw an interesting instrument on e-bay and placed auto-bid with $250 as a limit....
I have explained that - first I placed $55 bid and then decided to place $250 auto-bid a few seconds later.

Thanks, I interpreted your opening post as meaning you placed one single bid of $250.
Title: Re: Is Ebay rigging bids?
Post by: I wanted a rude username on February 14, 2020, 11:08:30 pm
see first line after sub-title "Are noon and midnight referred to as 12 a.m. or 12 p.m.?"

I already mentioned that technicality, and the practice is that every device that tells the time in this way (12 hour with AM/PM indicator) flips the indicator at the same time that the hour becomes 12.

Extraordinary claims require extraordinary evidence. Show us a single instance of a device that does not behave this way and we might believe you.

However, this is a distraction from all the other problems inherent in the 12-hour system. And it raises the question: why is a Croatian using eBay in 12-hour time, in the US Pacific timezone?
Title: Re: Is Ebay rigging bids?
Post by: jmelson on February 14, 2020, 11:33:03 pm
eBay uses "dutch bidding".  This is where the highest bidder wins the auction, but the winning PRICE is that of the 2nd highest bidder.  If two bidders offer the same bid, the earlier of those wins.
So, A bids $55, then later B bids $75.  B wins, but he pays $55 (or $55 plus the next price increment at that price level, which can be just a couple Dollars.)

Jon
Title: Re: Is Ebay rigging bids?
Post by: Stray Electron on February 15, 2020, 12:03:03 am

Yes, you are right -  AM/PM thing messed it up, but that's correct sequence... It would be too obvious - but now when I think of it - since e-bay charges a
percentage of sale, it's in their interest to get the highest price possible. When you enter auto-bid value, it's pretty easy to manipulate bidding process,
since you can't see actual account names (and links can point to basically anything). Say, you enter $500 as your maximum bid, algorithm can decide to
create a few fake bids and pump out more money from you than you should actually pay as long as the final amount is less or equal to $500.
You do it randomly, with various end-price differences and at various times, so there won't be visible pattern. Randomize the whole process good enough
and buyers would not  be able to spot it, sellers does not care since they will get more money for their stuff and everybody is happy... Best of all - you can't be caught !
Of course, if buyer is not using auto-bid then the whole scheme falls apart, but I guess there's a lot users using auto-bid, as you normally cant' spend the whole
day looking at e-bay.
Or I am just paranoid?

  yes, I think you're being paranoid.  Ebay could technically run up the bid to get a higher profit but the problem would be that since there was no real buyer, then the item would never be paid for and in that case, the seller would refuse to pay E-bay.  So end the end, E-bay would make nothing instead of a small amount.

   It would only take a few instances of non-existant buyers before the sellers caught on and once the word got around, everyone would stop doing business on E-bay.
Title: Re: Is Ebay rigging bids?
Post by: TerraHertz on February 15, 2020, 12:45:43 am
  yes, I think you're being paranoid.  Ebay could technically run up the bid to get a higher profit but the problem would be that since there was no real buyer, then the item would never be paid for and in that case, the seller would refuse to pay E-bay.  So end the end, E-bay would make nothing instead of a small amount.

   It would only take a few instances of non-existant buyers before the sellers caught on and once the word got around, everyone would stop doing business on E-bay.

I agree. But still never bid on ebay other than via a snipe service. There are multiple advantages - avoiding bidding wars and the stress that causes, not signalling your interest, eliminating all this waste of time wondering about bid sequences and cheating (for eg, seller bidding you up), saving my time by not having to pay attention to the item during the bidding period, etc.

Title: Re: Is Ebay rigging bids?
Post by: Deni on February 15, 2020, 07:46:45 am
Quote
And it raises the question: why is a Croatian using eBay in 12-hour time, in the US Pacific timezone?

Well, that's beyond me. If there's an option to change that, I can't find it - do you know how to change time display format as a buyer?
Title: Re: Is Ebay rigging bids?
Post by: Deni on February 15, 2020, 07:54:20 am
Quote

  yes, I think you're being paranoid.  Ebay could technically run up the bid to get a higher profit but the problem would be that since there was no real buyer, then the item would never be paid for and in that case, the seller would refuse to pay E-bay.  So end the end, E-bay would make nothing instead of a small amount.


OK, imagine this scenario - item initial price is $25, I enter auto-bid amount of $100. Now I am the highest bidder with $25. Then some "robot" with fake account kicks in and places auto-bid to $90.
Who will win that auction and what will be the end-price? Me, with end price of $91. And how can you tell that it was not a real bidder? You can't and since I will pay for the item seller won't know either.
Title: Re: Is Ebay rigging bids?
Post by: I wanted a rude username on February 15, 2020, 08:09:42 am
Ah, my mistake: the various ebay.ccTLD sites (ebay.co.uk, ebay.com.au, ebay.fr, etc. (https://blog.linnworks.com/international-ebay-sites-list)) are localised for timezone and time format, but ebay.hr (and also ebay.eu) just redirects to ebay.com.

eBay doesn't support changing either the timezone or time format on any site, even ebay.com.
Title: Re: Is Ebay rigging bids?
Post by: donotdespisethesnake on February 15, 2020, 09:23:16 am
Quote
They are unambiguous. They are just illogical to us, because we are aware of the concept of zero.

Well, NIST does think so (https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs (https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs)) - see first line after sub-title "Are noon and midnight referred to as 12 a.m. or 12 p.m.?"
And I take them as pretty good authority on the subject  ;)

I think that FAQ is badly worded, because they then proceed to completely contradict themselves and give an unambiguous definition: "[the time at] the shortest measurable duration after noon should be designated as p.m.". According to NIST, the shortest measurable duration is about 10^-15 seconds, which in human terms can be specified as "instantly".

What they really mean is that "people are often confused by am and pm", which is unambiguously true.
Title: Re: Is Ebay rigging bids?
Post by: peter-h on February 15, 2020, 10:48:32 am
"A sniping service is only useful to that emotionally weak people who can't stop bidding and that take it as a personnel challenge when someone outbids them"

Yet, that is precisely the biggest problem with Ebay. Most bidders are amateurs who just can't resist...

That is why one should decide the max one is prepared to pay, and esnipe it. I have been using esnipe.com for years. I set mine to t minus 5 seconds, to beat the t minus 6 seconds which a lot of other esnipers use :)
Title: Re: Is Ebay rigging bids?
Post by: I wanted a rude username on February 15, 2020, 01:29:00 pm
I set mine to t minus 5 seconds, to beat the t minus 6 seconds which a lot of other esnipers use

Leaving less time thwarts manual bidders who might otherwise react to your bid.

It only disadvantages you against other snipers ... in the rare case that they snipe exactly the same price.