climbing_vine
Well-known
N=30 is generally all that is needed for a p<.05.
If, and only if, you're dealing with a truly random sample of a larger population, which isn't evident in the eBay case, especially for niche items. Possible, but not necessarily so.
Estimates are running as high as 90% in certain areas (like laptops), though of course eBay will not reveal the data to create a truly accurate picture. I found this paper interesting:
http://tinyurl.com/myu64f
First, because it's from four years ago, and we know the problem is much worse now; second, because they found that in certain conditions shill bidding actually seemed to artificially *reduce* winning bids. Which is still a distortion, but not the one I expected! I'd love to see an update on this sort of work.
thomasw_
Well-known
Hahahahahehehehehehehehehahahahahahahahahahahahahahahahaaaaaaahahahhahahahhahahhahaaahehehehehe!!!!!!! O man I haven't had a chuckle raging full-on in a long time, Gumby. That is a classic post, one of the best ever
Through tears of laughter, Thanks heaps Gumby!Gumby
Veteran
Me too... I'd love to see it updated but doubt that a few years changes human behaviour. I've seen this research before... in fact, I think it was you who emtnioned it the first time I looked it over. As an experimental study I find it quite interesting. As a statment of the amount of shill bidding actually occurring on ebay I guess I'm still looking for vaidated numbers. Like you, I've seen shill bidding but I ahve not seen them at waht I consider to be alarming levels. Maybe I'm just not hanging out in the product lines that are prone to large amounts of bidding fraud. Likewise, I've also seen completed sales that were "mysteriously" re-listed... sometimes with a reasonable explanation but more often with a unbelievable explanation. Again, it has not been at levels high enough for me to totally discount the ebay compeleted sales as a source of "comparable sales". Even real estate comps have some bad data; doing any kind of research using recent sales requires some discretion. Weeding them out, and ensuring that "comps" really are comparable is part of the market research activity.
Gumby
Veteran
My pleasure... I consider it a contribution to the RFF community!
shadowfox
Darkroom printing lives
Wow, this is one lively thread.
I'm just a software geek and here's one suggestion:
Allow the seller to delete negative comments themselves. In return, they have to provide a reason for the deletion, and they are capped at three deletions per ad.
Why this method?
#1: The seller can police their own ads, moderators are not obligated to babysit ads. If I were in joe's shoes, I'd be miffed as well. Hopefully scanning reasons for deletion is way less work than monitoring all ads.
#2: The seller must provide a reason. I as a seller, paid my five dollars, I can delete up to three offensive comments from my ads, in return I give a reason of the deletion, which can be overturned by the moderators if they choose to.
#3: Why cap it at three? because if I get more than three negative comments in my ad, chances are someone is out to get me, and deleting comments are no longer the proper way to deal with that. Reporting it to Stephen may be more appropriate at that point.
#4: This will leave positive comments in place. Being useful and helpful.
I'm just a software geek and here's one suggestion:
Allow the seller to delete negative comments themselves. In return, they have to provide a reason for the deletion, and they are capped at three deletions per ad.
Why this method?
#1: The seller can police their own ads, moderators are not obligated to babysit ads. If I were in joe's shoes, I'd be miffed as well. Hopefully scanning reasons for deletion is way less work than monitoring all ads.
#2: The seller must provide a reason. I as a seller, paid my five dollars, I can delete up to three offensive comments from my ads, in return I give a reason of the deletion, which can be overturned by the moderators if they choose to.
#3: Why cap it at three? because if I get more than three negative comments in my ad, chances are someone is out to get me, and deleting comments are no longer the proper way to deal with that. Reporting it to Stephen may be more appropriate at that point.
#4: This will leave positive comments in place. Being useful and helpful.
David Murphy
Veteran
I think more information is better than less. I think sellers need to get a thicker skin, show a little humor when confronted with aggressive comments, and be able to roll with the punches. I've seen too many hobby sites (not just in photography) start down the censorship path and pretty soon they reach the point where only "happy talk" is allowed - it's so boring!
By the way, good gear at market prices (or reasonably close) always sells itself quickly here despite negative comments or any other buyer comments used as "tactics" to clinch a sale. In fact the comments and discussion they generate attract attention and sometimes even help one sell an item (remember: there's no such thing as "bad publicity").
I personally have no objection to the sort of comments buyers make as a method to stake claim to a sale. The seller is in charge of to whom he/she sells to, so I hardly see this as an issue.
By the way, good gear at market prices (or reasonably close) always sells itself quickly here despite negative comments or any other buyer comments used as "tactics" to clinch a sale. In fact the comments and discussion they generate attract attention and sometimes even help one sell an item (remember: there's no such thing as "bad publicity").
I personally have no objection to the sort of comments buyers make as a method to stake claim to a sale. The seller is in charge of to whom he/she sells to, so I hardly see this as an issue.
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climbing_vine
Well-known
No doubt, but a few years does a lot to change the patterns of usage (and abuse) of a resource on the Internet.
Everyone would like that, but without eBay's co-operation it's unlikely to ever happen.
Yeah. I wouldn't suggest that they should be totally discounted, but I haven't seen anyone develop a model that takes the necessary factors into account to produce credible comps from eBay completed sales. I'm definitely not saying that the numbers are meaningless--I'm only saying that, without real study and a useful model, the common wisdom that eBay sales are a proper gauge of "the market" is not wise.
I'm sure that in some categories the eBay sale amounts are a usable guide. Especially when it comes to non-collectible, low-priced consumer goods from used contemporary video games to, I dunno, baseball gloves. I imagine those are relatively untainted because that's not where the margins are for either outright scammers or shills. But when we're talking rarer and/or more expensive items, it's a different story.
And that's not even to get into the fact that if something really is collectible, the market is notoriously hard to pin down. Real-world auction estimates have wide ranges, and it's common for things to sell outside the range on both ends. And to vary wildly from one auction to another depending on all sorts of variables (or just chance). Ebay, in those cases, isn't any more definitive than real-world auction sales--with all its problems, it's less so.
>I never complained, just did an internal "arrrghhh!" Should I kick and scream that they
>have no right in torpedoing "MY" auction watching and bidding? No. They're free to post
>whatever.
I've seen such heads-up threads at RFF before. When it is for a BIN, I've often come out with a great bargain and no RFF bidding wars. On several occasions, I can see that an RFF member is top bidder. I've PM'd the OP and politely ask that the thread be deleted, as it has done its job, and that leaving it up will invoke a bidding war among RFF members. So: lessons learned: politely ask that the thread be deleted, give a thankyou for the heads-up whether or not you are bidding on it, and state the reason for the request.
>have no right in torpedoing "MY" auction watching and bidding? No. They're free to post
>whatever.
I've seen such heads-up threads at RFF before. When it is for a BIN, I've often come out with a great bargain and no RFF bidding wars. On several occasions, I can see that an RFF member is top bidder. I've PM'd the OP and politely ask that the thread be deleted, as it has done its job, and that leaving it up will invoke a bidding war among RFF members. So: lessons learned: politely ask that the thread be deleted, give a thankyou for the heads-up whether or not you are bidding on it, and state the reason for the request.
George S.
How many is enough?
Sounds like too much ad, auction and thread monitoring and back and forth emails or PMs. Just don't bother to post these "heads up" notices and leave the whole ebay thing alone. If an RFF member is actively looking for something they need, then they have access to the ad without any help. Pointing ads out only causes fellow RFF-ers to bid against each other and also promotes GAS to people like me who probably didn't see the ad in the first place, nor realize there's something else they "need".
This thread a seems to carry a lot of people's ideas on how a classified ad "should be run". and how "threads should be posted". It really does not matter what they think, as long as the current rules are followed.
Allowed: posting heads-up threads. Allowed, sending PM's. If you do not like them, don't open the threads.
Allowed: Positive comments on a classified ad, posting "PM sent", "intent to buy", "Boy I wish I had some money for this, maybe next week if it is still here but probably will not be because Brian is always circling like a Vulture".
Allowed: asking for pricing advice in a thread in either buying or selling an item.
Not Allowed: Negative comments in ads.
Seems pretty simple to me.
Allowed: posting heads-up threads. Allowed, sending PM's. If you do not like them, don't open the threads.
Allowed: Positive comments on a classified ad, posting "PM sent", "intent to buy", "Boy I wish I had some money for this, maybe next week if it is still here but probably will not be because Brian is always circling like a Vulture".
Allowed: asking for pricing advice in a thread in either buying or selling an item.
Not Allowed: Negative comments in ads.
Seems pretty simple to me.
climbing_vine
Well-known
Something qualitative like "negative" just isn't a good idea in rules, because reasonable people will disagree about what precisely is negative, and from whose perspective.
> Something qualitative like "negative" just isn't a good idea in rules because reasonable
> people will disagree about what precisely is negative, and from whose perspective.
The sign bit would be set to "1". Thus a comment that is NOT positive or neutral (zero) regarding the sale is a negative. It does not matter if the idea in the rules is good or bad, it is still in the rules.
Reasonable people should be able to read the rules which are clear-cut. It does not matter if they agree with them or not. If you do not agree with the rules, do not use the RFF ads. You can open a thread up and Rant about it, like JOE has done here.
> people will disagree about what precisely is negative, and from whose perspective.
The sign bit would be set to "1". Thus a comment that is NOT positive or neutral (zero) regarding the sale is a negative. It does not matter if the idea in the rules is good or bad, it is still in the rules.
Reasonable people should be able to read the rules which are clear-cut. It does not matter if they agree with them or not. If you do not agree with the rules, do not use the RFF ads. You can open a thread up and Rant about it, like JOE has done here.
rickp
Well-known
while discussing and proposing changes in the classified ads, is there a way to get the "sold" items removed more quickly. they clutter, and may reduce the attention given to items still available.
thanks (my 2 cents)
rick
thanks (my 2 cents)
rick
George S.
How many is enough?
I'd be happy to see more sellers hitting the "sold" icon after the sale. I'd bet that the majority of sales are completed using PayPal anyway, so there's not that many people waiting for the check to arrive or even clear. Seems many don't even know the "sold" thing is even there, or they don't care, figuring the ad will go just away sooner or later to wherever old ads get sent to.
I've contacted some sellers only to have them tell me I'm 4th in line. Jeez, I may be getting slow but I didn't think I was THAT slow....
I've contacted some sellers only to have them tell me I'm 4th in line. Jeez, I may be getting slow but I didn't think I was THAT slow....
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Ron (Netherlands)
Well-known
Advice: don't try to be like others (Ebay, Getdpi or the wacky Leica User Forum ad-section), but keep what you have now in order to distingish from others. That is why I like the classifieds, because of the comments (pos and critical). If I want something else, I already have it at the other fora.
George S.
How many is enough?
Has ebay really made it possible? I was cheated a number of years ago on an international purchase by a seller from the Netherlands- it was an intentional rip-off, not a mistake, as I sent $75 for a used Olympus OM body that was supposed to be in excellent condition, fully operational, etc... and he did send me an OM body, but a completely grimy, dirty, pitted, rusted, jammed shut and obviously not working piece and I posted negative feedback after I tried to resolve it first with him. [ He gave me the reply- It was working fine when I put it in the box for shipping! ] [ I know, for $75 I should have just forgotten about it, and if it was simply a disagreement over condition and not a fraud I would have. ] He posted an unintelligible negative on me, then changed his ebay name shortly thereafter. So I had this 1 negative on my record, and the negative I posted for him did not follow him to his new name, so other ebayers had no way to connect the two.
I asked ebay either to remove his negative, both negatives, or at least link the one I posted to his new name. I asked them this several times over many years and each time they told me "Sorry, there's nothing we can do." It finally disappeared not too long ago, I imagine when ebay redid things and made it impossible for sellers to leave negative comments for buyers.??
I asked ebay either to remove his negative, both negatives, or at least link the one I posted to his new name. I asked them this several times over many years and each time they told me "Sorry, there's nothing we can do." It finally disappeared not too long ago, I imagine when ebay redid things and made it impossible for sellers to leave negative comments for buyers.??
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