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Demian Rusakov
Demian Rusakov


An auction is usually a process of buying and selling goods or services by offering them up for bids, taking bids, and then selling the item to the highest bidder or buying the item from the lowest bidder. Some exceptions to this definition exist and are described in the section about different types. The branch of economic theory dealing with auction types and participants' behavior in auctions is called auction theory.


The open ascending price auction is arguably the most common form of auction and has been used throughout history.[1] Participants bid openly against one another, with each subsequent bid being higher than the previous bid.[2] An auctioneer may announce prices, while bidders submit bids vocally or electronically.[2]

Auctions have been recorded as early as 500 BC.[3] According to Herodotus, in Babylon, auctions of women for marriage were held annually. The auctions began with the woman the auctioneer considered to be the most beautiful and progressed to the least beautiful. It was considered illegal to allow a daughter to be sold outside of the auction method.[4] Attractive maidens were offered in a forward auction to determine the price to be paid by a swain, while unattractive maidens required a reverse auction to determine the price to be paid to a swain.[5]

Auctions took place in Ancient Greece, other Hellenistic societies, and also in Rome.[6] During the Roman Empire, after a military victory, Roman soldiers would often drive a spear into the ground around which the spoils of war were left, to be auctioned off. Slaves, often captured as the "spoils of war", were auctioned in the Forum under the sign of the spear, with the proceeds of sale going toward the war effort.[4]

The Romans also used auctions to liquidate the assets of debtors whose property had been confiscated.[7] For example, Marcus Aurelius sold household furniture to pay off debts, the sales lasting for months.[8] One of the most significant historical auctions occurred in 193 AD when the entire Roman Empire was put on the auction block by the Praetorian Guard. On 28 March 193, the Praetorian Guard first killed emperor Pertinax, then offered the empire to the highest bidder. Didius Julianus won the auction for the price of 6,250 drachmas per guard,[9][10][11] an act that initiated a brief civil war. Didius was then beheaded two months later when Septimius Severus conquered Rome.[7]

From the end of the Roman Empire to the 18th century, auctions lost favor in Europe,[7] while they had never been widespread in Asia.[4] In China, the personal belongings of deceased Buddhist monks were sold at auction as early as seventh century AD.[5]

The London Gazette began reporting on the auctioning of artwork in the coffeehouses and taverns of London in the late 17th century.The first known auction house in the world was the Stockholm Auction House, Sweden (Stockholms Auktionsverk), founded by Baron Claes Rålamb in 1674.[14][15] Sotheby's, currently the world's second-largest auction house,[14] was founded in London on 11 March 1744, when Samuel Baker presided over the disposal of "several hundred scarce and valuable" books from the library of an acquaintance. Christie's, now the world's largest auction house,[14] was founded by James Christie in 1766 in London[16] and published its first auction catalog that year, although newspaper advertisements of Christie's sales dating from 1759 have been found.[17]

The development of the internet has led to a significant rise in the use of auctions, as auctioneers can solicit bids via the internet from a wide range of buyers in a much larger variety of commodities than was previously practical.[21] In the 1990s, the multi-attribute auction was invented to negotiate extensive conditions of construction and electricity contracts via auction.[22][23] Also during this time, developed the Yankee auction as its trademark.[24] In the early 2000s, the Brazilian auction was invented as a new type of auction to trade gas through electronic auctions for Linde plc in Brazil.[25][26]With the emergence of the internet, online auctions have developed, with eBay being the most typical example. For example, if someone owns a rare item, they can display the item through an online auction platform. Interested parties may place bids, with the highest bidder winning the opportunity to purchase the item. Online auctions allow more people to participate and also make traditional auction theory more complex.[27]

In 2008, the US National Auctioneers Association reported that the gross revenue of the auction industry for that year was approximately $268.4 billion, with the fastest growing sectors being agricultural, machinery, equipment, and residential real estate auctions.[31]

Auctions come in a variety of types and categories, which are sometimes not mutually exclusive. Typification of auctions is considered to be a part of Auction theory.[36] The economists Paul Milgrom and Robert B. Wilson were awarded the 2020 Nobel Prize for the introduction of new auction types (or formats).[37] Auction types share features, which can be summarized into the following list.

Auctions can differ in the number and type of participants. There are two types of participants: a buyer and a seller. A buyer pays to acquire a certain good or service, while a seller offers goods or services for money or barter exchange. There can be single or multiple buyers and single or multiple sellers in an auction. If just one seller and one buyer are participating, the process is not considered to be an auction.[38][39][40]

A double auction is a combination of both forward and reverse auctions. A Walrasian auction or Walrasian tâtonnement is a double auction in which the auctioneer takes bids from both buyers and sellers in a market of multiple goods.[44] The auctioneer progressively either raises or drops the current proposed price depending on the bids of both buyers and sellers, the auction concluding when supply and demand exactly balance.[45] As a high price tends to dampen demand while a low price tends to increase demand, in theory there is a particular price somewhere in the middle where supply and demand will match.[44] A Barter double auction is an auction where every participant has a demand and an offer consisting of multiple attributes and no money is involved.[46] For the mathematical modelling of satisfaction level, Euclidean distance is used, where the offer and demand are treated as vectors.

Multiunit auctions sell more than one identical item at a time, rather than having separate auctions for each. This type can be further classified as either a uniform price auction or a discriminatory price auction. An example for them is spectrum auctions.

A combinatorial auction is any auction for the simultaneous sale of more than one item where bidders can place bids on an "all-or-nothing" basis on "packages" rather than just individual items. That is, a bidder can specify that they will pay for items A and B, but only if they get both.[56] In combinatorial auctions, determining the winning bidder(s) can be a complex process where even the bidder with the highest individual bid is not guaranteed to win.[56] For example, in an auction with four items (W, X, Y and Z), if Bidder A offers $50 for items W & Y, Bidder B offers $30 for items W & X, Bidder C offers $5 for items X & Z and Bidder D offers $30 for items Y & Z, the winners will be Bidders B & D while Bidder A misses out because the combined bids of Bidders B & D is higher ($60) than for Bidders A and C ($55). Deferred-acceptance auction is a special case of a combinatorial auction.[57]

Another special case of a combinatorial auction is the combinatorial clock auction (CCA), which combines a clock auction, during which bidders may provide their confirmations in response to the rising prices, with a subsequantial sealed bid auction, in which bidders submit sealed package bids. The auctioneer uses the final bids to compute the best value allocation and the Vickrey payments.[58][59]

Generalized first-price auctions and Generalized second-price auctions offer slots for multiple bidders instead of making a single deal. The bidders get the slots according to the ranking of their bids. The second-price ruling is derived from the Vickrey auction and means the final deal sealing for the number one bidder is based on the second bidder's price.

A No-reserve auction (NR), also known as an absolute auction, is an auction in which the item for sale will be sold regardless of price.[60][61] From the seller's perspective, advertising an auction as having no reserve price can be desirable because it potentially attracts a greater number of bidders due to the possibility of a bargain.[60] If more bidders attend the auction, a higher price might ultimately be achieved because of heightened competition from bidders.[61] This contrasts with a reserve auction, where the item for sale may not be sold if the final bid is not high enough to satisfy the seller. In practice, an auction advertised as "absolute" or "no-reserve" may nonetheless still not sell to the highest bidder on the day, for example, if the seller withdraws the item from the auction or extends the auction period indefinitely,[62] although these practices may be restricted by law in some jurisdictions or under the terms of sale available from the auctioneer.

A reserve auction is an auction where the item for sale may not be sold if the final bid is not high enough to satisfy the seller; that is, the seller reserves the right to accept or reject the highest bid.[61] In these cases, a set 'reserve' price known to the auctioneer, but not necessarily to the bidders, may have been set, below which the item may not be sold.[60] If the seller announces to the bidders the reserve price, it is a public reserve price auction.[63] In contrast, if the seller does not announce the reserve price before the sale, it is a secret reserve price auction.[64] However, potential bidders may be able to deduce an approximate reserve price, if one exists at all, from any estimate given in advance by the auction house. The reserve price may be fixed or discretionary. In the latter case, the decision to accept a bid is deferred to the auctioneer, who may accept a bid that is marginally below it. A reserve auction is safer for the seller than a no-reserve auction as they are not required to accept a low bid, but this could result in a lower final price if less interest is generated in the sale.[61] 041b061a72


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