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jbilliau
05-01-2009, 05:31 PM
Renlok,

What exactly is a dutch auction or what's the main difference? The ability to specify an # of items? I'm just wondering if it should be moved and made an on/off option in admincp to turn it on if being used by dutch users? Hmmm

Box Lot
05-01-2009, 09:34 PM
Ha!, not just for the Dutch!

Though I haven't tested the WeBid one, a Dutch auction usually involves multiples of the same item. There are lesser used definitions/procedures but I wont confuse things since I'm 99% certain this definition applies and it is the most often utilized in online auctions.

Bidders can bid on as many of the available items as they like (including just one).

At the end of the auction, the buyer who bid the highest wins the number of available items they bid on at the lowest price bid by everyone up to all available items . Any remaining items are sold to the bidders below until the quantity is gone. It's not quite that simple but that is the top level concept.

When the auction actually finishes it can get a little confusing.

Quick example. Let's say you have 10 widgets you want to sell and your opening/lowest price is $5.
Bidder 1 bids for 3 of them at a price of $6
Bidder 2 bids for 4 of them at a price of $5
Bidder 3 bids on 4 of them at a price of $5
Bidder 4 is hot for them and bids for 5 of them at a price of $15

The auction ends and the winning price is still $5 despite the bid of $15 because $5 was the lowest bid price.
Bidder 4 gets 5 for $5
Bidder 1 gets 3 for $5 (he bid more than 2 & 3 so takes precedence)
Bidder 2 gets the remaining 2 for $5
-------That's all 10----------
Bidder 3 is left out since bidder 2 bid at the same price first and ate up the remaining items.

So basically the higher bidders got priority but still received the items at lower than they bid due to the competition and resulting lowest bid.

In some cases, winners who win but do not win their total bid on number of items have the option to not make the purchase since in essence they did not win what they bid on. Not sure if that is in play with WeBid.

Hope I explained it right, hard to write down!

It is a popular auction style and deserves to be on a drop down auction type selection.

Box Lot
05-01-2009, 09:42 PM
Just an extra thought if you want to further clarify to your buyers.

This is a strong case for buyers to bid the maximum they are willing to pay and the maximum number of items they want.

Though this should always be the case, with Dutch auctions there is not proxy (automatic increases based on your maximum) bidding by the system and what you bid IS your bid.

renlok
05-01-2009, 10:26 PM
yeah thats a good explaination but Bidder 4 does have to pay $15 as if everyone just payed what the asking price was people could just bid rediculously high numbers just so they win

Box Lot
05-01-2009, 10:50 PM
Mmm, not usually but certainly you would know in the case of WeBid. Of course in that example it was $5 and I used that as a bid too which is confusing.

If you bid too low you (may) lose out.

Also, not in the best interest of the buyer to bid too high since they may be obligated to pay that price, particularly if no one else bids. Yes, you may win because of that but potentially at a price your not willing to live with.

Generally it is a combination of the competition, quantity available and opening bid that generates the final sales price.

Again, you would know with WeBid of course! but..

10 widgets you want to sell and your opening/lowest price is $5.
Bidder 1 bids for 3 of them at a price of $25
Bidder 2 bids for 4 of them at a price of $15
Bidder 3 bids on 4 of them at a price of $15
Bidder 4 is hot for them and bids for 5 of them at a price of $50

The auction ends and the winning price usually would be $15. Otherwise the remaining "under" bidders would get them cheaper than the top bidder.
Bidder 4 gets 5 for $15
Bidder 1 gets 3 for $15
Bidder 2 gets the remaining 2 for $15
Bidder 3 is still out of course.

Take your idea and just buyer 4 shows up and bids on all 10 for $1,000 each. He owes $10,000! Again, there is usually no incremented bidding and his $1,000 bid would go in as-is. This is actually a common mistake for buyers not familiar with how it works elsewhere when they are used to bidding their maximum, takes a little more savvy.

Again, could be me due to the difficulty of clearly explaining but this is how I'm used to having it work. Also hard to show examples with everything in play especially the quantity available (again especially in the case of the lowest winning bidder who gets the last shot at the items).

Box Lot
05-01-2009, 11:40 PM
-edited out comment to simplify post.

Box Lot
10-01-2009, 09:10 PM
Of course Renlok was correct and this does work different then most Dutch auctions I've been exposed to and I believe it is a better methodology at least for the seller.

Since it is a little confusing, I've tested the Dutch auction and here's what I find.

Using the latest example but only 3 buyers (since 4th was always left out anyway) and corrected information:
10 widgets you want to sell and your opening/lowest price is $5.
Bidder 1 bids for 3 of them at a price of $25
Bidder 2 bids for 4 of them at a price of $15
Bidder 3 bids on 4 of them at a price of $15.75 - Bidder 3 is forced to bid at least another increment higher, in my case, $15.75. So lowest bid in the scenario raises the new minimum bid, they can't be identical.

Here's how the winners pane out:
Bidder 1 gets his 3 and pays $25 each
Bidder 2 gets his 4 for $15.00 each
Bidder 3 gets 3 of his 4 bid on (10 limit reached) for $15.75 each.

Hope that clears it up for those who follow, this method is much more intuitive (way to go Renlok!) and easier to understand.

quadflash
19-11-2009, 08:53 AM
Since I like the way Box Lot mentioned in his reply that items will distribute to highest bidders with the lowest qualified bid price (same for all) before items run out. I modified the cron.php as you can find in the attached file.

quadflash
19-11-2009, 02:23 PM
I did another modification to Dutch auction by adding reserved price. Here are steps.

1. in sell.tpl, remove [class="dutchhide"] from line 225
2. also in sell.tpl, move <!-- IF ATYPE_PLAIN eq 1 --> (line 416) to place between line 422 and 423.
3. in datacheck.inc.php, modify line 215 to

if ($with_reserve == 'yes' && (($atype == 1 && $reserve_price <= $minimum_bid) || ($atype == 2 && $reserve_price >= $minimum_bid)))

step 1&2 are used to display reserved price in selling pages
step 3 is for checking the proper setting of the price

Since it makes no sense for me that keeping bids below reserved price, I added a few lines also in datacheck.inc.php before line 269

//check for bid lower than reserved price
if ($bid < $Data['reserve_price'])
{
return '607';
}

waystar
22-02-2010, 09:52 PM
So basically the higher bidders got priority but still received the items at lower than they bid due to the competition and resulting lowest bid.


Or is this a better summary?

<So basically the higher bidders get priority but still received the quantity of items at a lower price than the highest bid on a first come first bid basis.>

Also, Box Lot, have run a test with 4 users yet to confirm this explanation. Is your explanation a assumption of how webid works regarding dutch auctions, or a fact?

I will test it either way, just wondering:)
Thanks for your input and time.

Box Lot
22-02-2010, 11:13 PM
Well, no, you didn't finish the thread where I was corrected on WeBid methodology. I followed this with a replacement example.

High bidder gets as many as they bid for at their high bid. What ever is left is then distributed to underbidders based on bid/quantity. Again the highest underbidder gets the number the bid on (provided any are left) at the price they bid, not the lowest bid. And so on.

From a sellers standpoint, and as Renlok noted, this prevents people making ridiculously high bids to guarantee winning as many as they want and at the less devious thinking other bidders lowest bid. It maximizes return for the seller.

My second/last scenario (http://www.webidsupport.com/forums/showthread.php?154-Dutch-Auction-Question&p=843&viewfull=1#post843) (#7) was verified with a test of the version at that time so I can only assume it still holds though I haven't redone any Dutch testing of any kind since.

I will once 1.0 is released which is when I plan to jump back into testing mode (taking a little break after a year!....I'm NOT Renlok after all and lack his stamina).

This is easy enough for anyone to test, just create a few users and a dutch auction. Once you've done the bidding just end it early for quick results.


EDIT: For those of you that subscribe to duplicating bit for bit what E*ay does (I do not, and strongly in some cases, they do do a lot wrong IMO which is why I'm here), it works as initially described here.


I think Renloks point is a strong one for doing it the WeBid way and it makes more sense to me.


Regardless of the methodology the truth for a user is that, as in all auctions, they should bid the maximum they are willing to pay and the number they want to win. Here too remember that there is no proxy bidding in a Dutch auciton, what you bid IS your bid. I recommend including this kind of note in your help section along with the explanation.

Personally as a seller I rarely do Dutch auctions unless the quantity is extremely large and the cost of goods is low. Time is a consideration for some of course but I have plenty to sell and I can pepper quantities in (or not if they sell poorly) from a lot from time to time.

Ha! Like you asked. :p

waystar
23-02-2010, 02:48 PM
Well, no, you didn't finish the thread where I was corrected on WeBid methodology. I followed this with a replacement example.

High bidder gets as many as they bid for at their high bid. What ever is left is then distributed to underbidders based on bid/quantity. Again the highest underbidder gets the number the bid on (provided any are left) at the price they bid, not the lowest bid. And so on.

From a sellers standpoint, and as Renlok noted, this prevents people making ridiculously high bids to guarantee winning as many as they want and at the less devious thinking other bidders lowest bid. It maximizes return for the seller.

My second/last scenario (http://www.webidsupport.com/forums/showthread.php?154-Dutch-Auction-Question&p=843&viewfull=1#post843) (#7) was verified with a test of the version at that time so I can only assume it still holds though I haven't redone any Dutch testing of any kind since.


#7
10 widgets you want to sell and your opening/lowest price is $5.
Bidder 1 bids for 3 of them at a price of $25
Bidder 2 bids for 4 of them at a price of $15
Bidder 3 bids on 4 of them at a price of $15.75 - Bidder 3 is forced to bid at least another increment higher, in my case, $15.75. So lowest bid in the scenario raises the new minimum bid, they can't be identical.

Here's how the winners pane out:
Bidder 1 gets his 3 and pays $25 each
Bidder 2 gets his 4 for $15.00 each
Bidder 3 gets 3 of his 4 bid on (10 limit reached) for $15.75 each.


Ok above is number #7
what does not make sense to me in this senerio is Bidder 3. Bidder three bids $15.75 and only gets 3 out of 4 items he bids on. For me it would seem more logical that since he is highest bidder, outbidding bidder 2; that bidder 3 should get 4 items and bidder 2 should only get 3 items since his bid is lower?

However you say somewhere in next thread #2


Bidder 3 is left out since bidder 2 bid at the same price first and ate up the remaining items.

So are you saying that bidder 3 high bid amount of 15.75 does not matter in this senerio since Bidder 2 was first in line to bid on items?

Or are you saying bidder 3 gets 4 items because his bid IS higher than bidder 2? And bidder 2 only gets 3 items regardless of who bid first?
Sorry I am confused..

Box Lot
23-02-2010, 07:51 PM
I would suggest you set up a few users on your site and try it, this can be a confusing format that is best illustrated in practice.

Segart
12-05-2010, 06:08 PM
I did another modification to Dutch auction by adding reserved price. Here are steps.

I try this adds, but nothing get. But i think it's good thought.

Pardeep Singh Ghuman
07-05-2013, 03:08 PM
nice one bro...can you help me to setup reverse auction site only using webid..i am struggling bro