Mise en page 1

"The word "auction" is derived from the Latin augeo which means "I augment".
For most of history, auctions have been a relatively uncommon way to negotiate
the exchange of goods and commodities before the seventeenth century...
Nonetheless, auctions have a long history, having been recorded as early as 500
B.C. 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. It was considered illegal to allow
a daughter to be sold outside of the auction method.
Transmission
13-2015
Auction Theory
During the Roman Empire, following military victory, Roman soldiers would often
drive a spear into the ground around which the spoils of war were left, to be
auctioned off. Later, 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 towards
the war effort. The Romans also used auctions to liquidate the assets of debtors
whose property had been confiscated. For example, Marcus Aurelius sold
household furniture to pay off debts, the sales lasting for months.
A significant auction occurred in Rome on March 23, 193 A.D. The Praetorian
Guard first killed emperor Pertinax, then offered the Empire to the highest bidder.
Didius Julianus outbid Sulpicianus for the price of 25,000 sesterces per guard (or
ten years worth of wages)... Upon his accession, Julianus immediately devalued
the Roman currency... " (from Wikipedia).
n°110
Contents of transmission number 13-2015 :
A number of albumen and silver prints with auction theory allusions
Auction theory digest (from Wikipedia online articles, bilingual)
The covers you have missed
uploaded at 3.15 pm
monday 30th march 2015
The e-bulletin presents books, albums, photographs and ancient
documents as they have been transmitted to us by their creators
and by the amateurs from past generations.
The physical descriptions, attributions, origins, place and
date of printing of books and photographs have been carefully
ascertained with collations and comparisons with other prints
or comparable samples (from our phototèque).
Number Thirteen of the weekly bulletin has been
uploaded on monday, 30th March at 15:15 (Paris time).
French captions are printed in black.
This transmission is dedicated to auction theory topics and theorems.
Ce bulletin suit un fil rouge : les différents systèmes d'enchères.
All the bulletins are available on our site:
www.photoceros.com / BTP
Upcoming uploads and transmissions : monday 6th April,
monday 13th April, monday 20th April, monday 27th April,
The books and photographs from all around the world are presented
in chronological order. It is the privilege of ancient and authentic things
to be presented in this fashion, mirroring the flow of ideas and creations.
All the items presented are available at the instant of transmission.
The prices are denominated in euro. Paypal is accepted. Priority is given
to the first outright purchase, confirmed by email to
[email protected]
To subscribe and receive the bulletin in .pdf format,
easily printable, or for remarks and suggestions:
Correspondance in Russian, Italian, Spanish, German, Turkish or English :
[email protected]
Phone (10am -5 pm) : (+33) 1.43.60.71.71
Rhinoceros & Cie
Studios Robespierre
71 rue Robespierre
93100 Montreuil
Semaine 13 : 30 mars - 5 avril 2015
103
Week 13 : March 30-april 5, 2015
Eugène Disdéri (1819-1889)
Henri Rochefort, a journalist in exile
Paris, c. 1868
Albumen carte-de-visite , Disderi printed name on mount.
Victor Henri Rochefort, Marquis de Rochefort-Luçay (1831-1913) was a
French politician. His father was legitimist but his mother's views were
republican. After experience as a medical student, a clerk at the Hôtel de
Ville in Paris, a playwright and a journalist, he joined the staff of Le Figaro in
1863; but a series of his articles brought the paper into collision with the
authorities and caused the termination of his engagement.
On leaving Le Figaro Rochefort determined to start a paper of his own, La
Lanterne. The paper was seized on its eleventh appearance, and in August
1868, Rochefort was fined 10,000 francs, with a year's imprisonment.
He then published his paper in Brussels, whence
it was smuggled into France. Printed in French,
English, Spanish, Italian and German, it went the
round of Europe. After a second prosecution he
fled to Belgium...
A series of duels, of which the most famous was
one fought with Paul de Cassagnac à propos of
an article on Joan of Arc, kept Rochefort in the
public eye.”
150 euros
Ce portrait peu commun révèle un léger strabisme
Semaine 13 : 30 mars - 5 avril 2015
104
Week 13 : March 30-april 5, 2015
Georges Révoil (1852-1894)
On the way to Cape Guardafui
Gulf of Aden, 1878
Vintage albumen, 120x160 mm, original mount with a
short caption in pencil by the explorer : “Alleyah”.
Rare example of one of the first photographs taken in
Somalia, with an evocation of the most mysterious years
of the life of French poet Arthur Rimbaud in Aden and
possibly Somalia.
“My dad…was an employee of Father Suel, owner of
the Suel Hotel who needed hands to send a small
expedition to loot the wreck in Cape Gardafui where a
ship was stranded. They were three or four I think,
sitting on chairs every evening on one of the sides at the
entrance of the hotel, as I was on the other side with
friends. There was an Arthur Rimbaud among them and
I always thought it was the poet. If I ever reach the
explorer George Révoil I'll be able tell you what I don't
tell you here - or what's different.” Jacques Desse,
Rimbaud pilleur d’épaves ? “À propos de deux lettres
[d’Émile Deschamps] conservées par le muséebibliothèque Arthur Rimbaud”, Revue des Deux
Mondes, septembre 2012.
1.200 euros
"Alloùla and Bender Ziyâda are the only two cities where there are stone constructions"(“Alloùla et
Bender Ziyâda sont les deux seules villes, où il y ait des constructions en pierre” (Georges Révoil,
Voyage au Cap des Aromates, p. 181).
Semaine 13 : 30 mars - 5 avril 2015
105
Week 13 : March 30-april 5, 2015
Georges Révoil (1852-1894)
Las Khorey Fort
Warsangali Sultanate, 1878
Vintage albumen, 120x160 mm, original mount with a short
caption in pencil by the explorator : “Las Goree, le fort
Mohammed Abdi où je logeais”, spots, strong contrast.
A nice example of one of the first photographs in Somalia.
“After nightfall, we see Râs Orbé (en çomali Dourboh), a
small stronghold and village in the west before Bender
Merâya. The high mountains circling Râs Orbé are covered
with vegetation, sharp peaks a few hundred feet high, they
form a small creek in the center of which stand the
stronghold and the dwellings” (Georges Révoil, Voyage au
Cap des Aromates (Afrique orientale), 1877-1878, Paris,
1880, p. 8).
3.000 euros
“I still see these huge mountains, the corbels of the towers made from adobe draw the ridges like
a dark line” (“Je revois encore ces grandes montagnes, ces tours en pisé dont les corbeaux
dessinent les faîtes comme une ligne noire” (G. Révoil, Voyage au Cap des Aromates, p. 123).
Semaine 13 : 30 mars - 5 avril 2015
106
Week 13 : March 30-april 5, 2015
Georges Buffotot (Studio in Sevres)
Quartermaster Lebriz
Brazzaville, 1885-(1925)
Silver print, 171x115 mm, printed in 1925, stamped at verso, from a
mysterious negative brought back from Congo in the mid 1880’s, and
captioned later by an eye-witness (the priest of the expedition ?) : “Le
Quartier-maître Lebriz, premier Européen décédé et inhumé à Brazzaville
en juillet 1885, probablement le 9 — c’était un lundi”.
A rare portrait of the worker who built the first houses and streets of
Brazzaville : “The city was founded by an Italo-French explorer, Pierre
Savorgnan de Brazza, after whom the city was named. French control over
the area was made official by the Berlin Conference of 1884.”
The final location of Brazzaville is chosen on may 1884. After leaving the
king Makoko, Brazza and his companions settle on a plain thirty meters
above the Congo. It must be built: " we got organized in a hurry: brushing
with machete, clearing the view, creation of necessary pathways, searching
for construction material in the forest. We'll live a long time under canopies
or makeshift tarpaulins.” (Charles de Chavannes). on the 30th september
1884, the first wwoden house is finished. The quartermaster is the
constructor of the first houses in Brazzaville.
400 euros
Semaine 13 : 30 mars - 5 avril 2015
107
Week 13 : March 30-april 5, 2015
French Press Agency
Trotsky and fourteen SPb Soviet members
Enroute for Siberia, winter 1906-(1925)
Silver press tinted print, 1920’s reproduction, 140x105 mm, captioned.
Early reproduction of an untraced original, showing in fact a full mounted
pop print on a decorated board. Circumstances of the photography session
hardly survived. Indeed, “The chance of factual truth surviving the onslaught
of power are very slim indeed, it is always in danger of being manœuvered
out of the world not only for a time, but potentially forever... [Photographic
prints as] Facts and events are infinitely more fragiles things than axioms,
discoveries, theories..." (Hannah Arendt, Truth and Politics).
Auction theory : the linkage principle, “the linkage principle is a finding
which states that auction houses have an incentive to pre-commit to
revealing all available information about each lot, positive or negative”.
400 euros
“More than fifty members of the St Petersburg Soviet were arrested after the failure
of the Russian Revolution of 1905 and kept in prison for months without trial...
Trotsky had been the principal spokesman. Now in his late twenties, he quite liked
incarceration, or said he did, because it gave him time to himself to read and think.
His wife Natalia visited him, he was given practically all the books he asked for, his
writings were smuggled to the outside world in his lawyer’s briefcase... The trial on
charges of armed insurrection began at last in October 1906. Held in open court,
it attracted much attention and Trotsky seized the opportunity to tell the court that
the ‘working masses’ had every reason to rebel, that the government’s programme
for reform of the system was a shame and that the government was responsible for
the bloodshed. The court let most of the defendants go, but Trotsky and fourteen
others were sentenced to exile for life”.(CF. Richard Cavendish, History Today).
Semaine 13 : 30 mars - 5 avril 2015
108
Week 13 : March 30-april 5, 2015
Soviet Photographer
Chess Tournament
Moscow, c. 1930
Vintage silver print, 240x180 mm, stamps and agency captions at verso
An interesting composition for an interesting competition.
Auction theory : Auction model, “A game-theoretic auction model is a
mathematical game represented by a set of players. When it is necessary to
make explicit assumptions about bidders' value distributions, most of the
published research assumes symmetric bidders. This means that the
probability distribution from which the bidders obtain their values (or
signals) is identical across bidders. In a private values model which assumes
independence, symmetry implies that the bidders' values are independently
and identically distributed.”
1.200 euros
Semaine 13 : 30 mars - 5 avril 2015
109
Week 13 : March 30-april 5, 2015
Circle of Richard Archbold (1907-1976)
Idenburg River Crocodile
Dutch New Guinea (Papua), january 1937
Vintage silver print, 210x255 mm, dated “37/1/5” and
captioned in pencil.
“The Taritatu River is a river in the northern part of the
Indonesian province of Papua. During the Dutch
colonial era, it was known as the Idenburg River.
Eventually, it meets the Tariku River, and at this
confluence the two rivers become the Mamberamo
River, one of the largest rivers on New Guinea”.
An early Papua modernist image ?
300 euros
Cf. Research Library of the American Museum of
Natural History (AMNH).
Auction theory : Buyer’s Remorse. The phenomenon of
buyer’s remorse has been generally associated with the
psychological theory of cognitive dissonance, a state of
psychological discomfort when at least two elements of
cognition are in opposition, and which motivates the
person to appease it by changing how they think about
the situation.
Semaine 13 : 30 mars - 5 avril 2015
110
Week 13 : March 30-april 5, 2015
Gordon Coster (1906-1988)
Advertising Studio Lab
Chicago, 1940’s
Vintage silver print, 200x250 mm, stamped, mint
condition
Auction : Sotheby’s sold in New York on december 2014
another photograph by this artist (“Bicycle Racer”) for
the sum of 16,250 USD (Hammer Price with Buyer's
Premium) with the comment : “This dynamic image,
which so captures the speed and excitement of track
cycling, was made by multi-faceted photographer
Gordon Coster. Like many of his generation, Coster
began his career working in the Pictorial mode, and his
photographs were frequently exhibited in the Camera
Club salons of the 1920s. In the late 1920s, he worked
for the Underwood & Underwood agency in New York.
He settled in Chicago in the 1930s and worked there as
a photojournalist for LIFE, while also contributing images
to Fortune, Time, Scientific American, and other
magazines. He was asked by László Moholy-Nagy to
teach at Chicago’s famed Institute of Design in 1946,
and he taught there periodically through 1960, where
his primary focus was upon social documentary.”
1.500 euros
Auction theory : Under conditions of perfect information, game theory shows that the expected
income of the seller is an increasing function of the number of bidders. — Too big to fail again ?
Semaine 13 : 30 mars - 5 avril 2015
111
Emile Crevaux (Industrial photographer)
A Visual Catalogue of Toolboxes
Courbevoie, c. 1937-1939
9 silver prints, 180x240 mm, mounted and captioned; very decorative
unique set for the maquette of a catalogue for Saint-Chamond-Granat
factory, in Courbevoie.
Auction Theory : SOB, Suggested Opening Bid : There will usually be an
estimate of what price the lot will fetch. In an ascending open auction it is
considered important to get at least a 50-percent increase in the bids from
start to finish. To accomplish this, the auctioneer must start the auction by
announcing a SOB that is low enough to be immediately accepted by one
of the bidders. Once there is an opening bid, there will quickly be several
other bids submitted.
Experienced auctioneers will often
select a SOB that is about 45 percent
of the (lowest) estimate. Thus there
is a certain margin of safety to ensure
that there will indeed be a lively
auction with many bids submitted.
Several observations indicate that
the lower the SOB, the higher the
final winning bid. This is due to the
increase in the number of bidders
attracted by the low SOB”.
(9 prints) 450 euros
Week 13 : March 30-april 5, 2015
Semaine 13 : 30 mars - 5 avril 2015
112
Week 13 : March 30-april 5, 2015
Californian Photo
California First Oil Rafinery
Newhall, 1954
Vintage Silver print, 180x240 mm, caption
and date stamp at verso.
Where Oil replaced Gold. “Unlike the
competition to "The First California Gold
Discovery," to which Northern California
laid vociferous and popular claim until the
early 1930s, Newhall's position in the
Western development of the oil industry has
always been fully recognized. Here
California's oil industry was born, exactly in
Well No. 4, Pico Canyon Oilfield, located
about seven miles west of Newhall, in the
Santa Susana Mountains, the first successful
oil well in the Western United States.
Drilled in 1876, it turned nearby Newhall
into a boomtown and also spawned a
smaller boomtown called Mentryville
adjacent to the drilling site. Well No. 4
continued in operation for 114 years until it
was capped in 1990 and the Mentryville
ghost town is now open to the public as a
historic park.”
300 euros
Auction theory : Although less publicly visible than antiques, economically important are the oilfields auctions.
Semaine 13 : 30 mars - 5 avril 2015
113
Circle of Paris Theaters
A Mise en abyme photographic kit
Paris, circa 1900
The kit consist of :
1. The actress portrait, with an actor, silver print, c.1900 in a gilded frame
2. Her original 18th century style gown consisting of two pieces, a silk skirt
with an attached bodice, sewn in the 1890’s and present in the photograph.
The name of the actress could be traced with patience.
"The Auctioneer" is a 1956 country song by Leroy Van Dyke. The song talks
of a young Arkansas boy who would skip school and visit a local auction
barn. Becoming mesmerized by the auction chant, he decides he wants to
be an auctioneer, regularly practicing the chant behind the family barn.
Though his parents are initially unhappy with
his career choice, eventually they relent, but
(not wanting their family name to be ruined
by poor auctioneering skill) they send him to
auction school to properly learn the trade.
He returns home a full-fledged auctioneer.
Over time, he becomes "the best in all the
land", having so much business that he ends
up buying "a plane to get around".
Gown + framed portrait : 450 euros
Week 13 : March 30-april 5, 2015
Les différents systèmes d’enchères
Auction Theory
N°1. Enchères à un tour sous pli cacheté
N°1. First-price sealed-bid auctions
Aussi appelées enchères scellées au premier prix. Chaque enchérisseur
remet une enchère sous enveloppe ou électroniquement au commissairepriseur qui examine toutes les offres. L’objet est attribué au plus offrant, qui
paie son montant proposé.
Or Blind auctions. Auctions in which bidders place their bid in a sealed
envelope and simultaneously hand them to the auctioneer. The envelopes
are opened and the individual with the highest bid wins, paying the amount
bid.
Procédé classique utilisé lors des appels d'offre pour les marchés publics
entre autres ou encore pour les droits minéraux et de forage dans les terrains
de l'État.
These auctions are commonly called tendering for procurement by
companies and organisations, particularly for government contracts and
auctions for mining leases.
N°2. Enchères au second prix sous pli cacheté (Vickrey)
N°2. Sealed-bid second-price auction (Vickey auction)
À partir de la même procédure, l’objet est adjugé au plus offrant, qui paie
le prix offert par le deuxième meilleur enchérisseur. Ce système conduit les
acteurs à proposer leur juste prix pour l'objet en jeu.
Identical to the sealed first-price auction except that the winning bidder
pays the second-highest bid rather than his or her own.
Procédé utilisé pour la vente de timbres de collection depuis le XIX siècle,
et par Google dans la vente de ses espaces publicitaires.
Although extremely important in auction theory, in practice Vickrey auctions
are rarely used in non-automated contexts as the proxy bidding system used
by the Internet auction site eBay.
N°3. Enchère ascendante ou enchère anglaise
N°3. English auction
La plus populaire et la plus commune à tous : le commissaire-priseur
commence avec un prix de départ, chaque intéressé offre dès lors
successivement un prix plus élevé, tout en respectant une surenchère
minimum (aussi appelé incrément minimal). Le bien est attribué au candidat
le plus offrant. L’enchère à la bougie consiste à fixer un temps limite pour
formuler les offres : quand la bougie s’éteint, les enchères sont terminées.
Also known as an open ascending price auction. This type of auction is
arguably the most common form of auction in use toda. An auctioneer may
announce prices, bidders may call out their bids themselves or bids may be
submitted electronically with the highest current bid publicly displayed and
the highest bidder pays his bid.
e
Procédé courant dans les salles de ventes.
Commonly used for selling goods, most prominently antiques and artwork.
Les différents systèmes d’enchères
Auction Theory
Variante 3b : Enchère ascendante japonaise
Variation 3b : Japanese auction
Le commissaire-priseur commence avec un prix de départ, chaque intéressé
offre successivement un prix plus élevé. Le bien est attribué au candidat “le
plus offrant” à un prix de cession égal à l'offre la plus élevée parmi celles
des candidats éliminés, appelé “deuxième prix”. Système stratégiquement
analogue à celui d'une enchère fermée au second prix.
An auctioneer may announce prices, bidders may call out their bids
themselves. But when the bidding starts no new bidders can join, and each
bidder must continue to bid each round or drop out. It has similarities to
the ante in Poker. The winner pays the second best offer. Similiraty with the
sealed-bid second price auction strategy.
Procédé courant dans les salles de ventes japonaises.
In use only in Japan.
N°4. Enchère descendante hollandaise
N°4. Dutch auction
Le commissaire priseur annonce un prix de départ supérieur a priori à l'offre
maximale de tous les candidats, puis l’abaisse par étapes, jusqu'à ce qu'un
candidat se déclare preneur (les offres des autres candidats restent, dans
cette procédure, inconnues). Stratégiquement équivalente à l'enchère
fermée au premier prix étant donné qu'un enchérisseur se fondera sur son
évaluation initiale du montant auquel il désire faire l'acquisition pour
remettre son offre.
Also known as an open descending price auction. the auctioneer begins
with a high asking price for some quantity of like items; the price is lowered
until a participant is willing to accept the auctioneer's price for some
quantity of the goods in the lot. If the first bidder does not purchase the
entire lot, the auctioneer continues lowering the price until all of the items
have been bid for or the reserve price is reached. Items are allocated based
on bid order; the highest bidder selects their item(s) first followed by the
second highest bidder, etc...
Ce procédé très rapide est utilisé pour la vente de denrées périssables,
comme, par exemple, aux Pays-Bas pour la vente des fromages et des fleurs
coupées et au Japon sur les marchés au poisson. En France aussi pour la
traditionnelle vente au cadran : les prix décroissent toutes les heures.
Dutch auctions, named for the best known example, the Dutch tulip
auctions, have also been used for perishable commodities such as fish and
tobacco.
Théorie : Enchère “All Pay”
Theory : All Pay auction
L'ensemble des compétiteurs doivent payer leur offre mais seul le
participant ayant remis la meilleure offre remporte l'enchère. Cela permet
de considérer les loteries comme des enchères en théorie des jeux.
All bidders must pay their bids regardless of whether they win. The highest
bidder wins the item. Primarily of academic interest, and may be used to
model lobbying or bribery or competitions such as a running race.
Les différents systèmes d’enchères
Auction Theory
Système optimal en théorie des jeux
Game Theory and Auctions
William Vickrey a analysé les propriétés de l’enchère au second prix dite
«enchère de Vickrey», dans laquelle le «gagnant», émetteur de l’offre la plus
élevée, paye le prix correspondant à la seconde meilleure offre.
Generally, the players are the buyer(s) and the seller. In the first model,
Vickrey considers two buyers bidding for a single item. Vickrey showed that
in the sealed first-price auction it is an equilibrium bidding strategy for each
bidder to bid half his valuation.
Le résultat de son célèbre travail a été repris et discuté par nombre de ses
successeurs. Selon William Vickrey, quoi que fassent les autres «joueurs»,
un enchérisseur a toujours intérêt à émettre une offre d’un montant égal à
son évaluation réelle de l’objet.
En effet, offrir un prix inférieur à sa disposition à payer diminue les chances
qu’a l’enchérisseur de remporter les enchères sans accroître le gain qu’il
réaliserait en cas de victoire (puisque le prix payé est indépendant du prix
annoncé). Inversement, annoncer un prix supérieur à son évaluation privée
accroît la probabilité de victoire mais expose l’enchérisseur à payer plus
qu’il n’est disposé à le faire («acheter à perte»). Ainsi, «dire la vérité» est
une stratégie strictement dominante, c’est-à-dire une stratégie qui offre à
l’enchérisseur des gains supérieurs aux autres stratégies, quel que soit le
comportement adopté par les autres «joueurs».
Cela correspond au sytème d’enchère N°2 : vente sur offre sous pli cacheté
au second prix, ainsi qu’au système d’enchère ascendante, N°3 et N°3b,
effectué de manière transparente et non faussé.
L’apport récent de la théorie des jeux dans les mécanismes d’enchères a
donné naissance à un des théorèmes les plus importants de la théorie des
enchères, le “Théorème d’équivalence des revenus”.
When it is necessary to make explicit assumptions about bidders' value
distributions, most of the published research assumes symmetric bidders.
This means that the probability distribution from which the bidders obtain
their values (or signals) is identical across bidders. In a private values model
which assumes independence, symmetry implies that the bidders' values
are independently and identically distributed, a very strong and theorical
assumption, indeed.
Revenue equivalence of the open ascending price (or English) auction and
sealed first price (or high-bid) auction.
In the open ascending price auction a buyer’s dominant strategy is to
remain in the auction until the asking price is equal to his value.
One of the major findings of auction theory is the celebrated revenue
equivalence theorem.
Early equivalence results focused on a comparison of revenue in the most
common auctions. The first such proof, for the case of two buyers and
uniformly distributed values was by Vickrey (1961). In 1979 Riley &
Samuelson (1981) proved a much more general result :
Les différents systèmes d’enchères
Auction Theory
Théorème d’équivalence des revenus
Revenue equivalence theorem
Dans la lignée des travaux de William Vickrey, Myerson et Riley-Samuelson
ont démontré en 1981 que les quatre enchères classiques définies ci-dessus
sont équivalentes pour le vendeur et souvent optimales.
Autrement dit, le vendeur n’aurait pas d’intérêt à choisir un mécanisme
d’enchère plutôt qu’un autre. Mais cette équivalence des revenus n’est
plausible que sous certaines hypothèses plus abstraites que réalistes :
— Les joueurs sont neutres face au risque : ils accordent la même valeur
au pari et à ses attentes.
— Les évaluations privées de chaque joueur sont tirées de la même
distribution de probabilité : symétrie des joueurs.
— Les acheteurs disposent avant la vente de la même information.
— Le prix d'adjudication, autrement dit la valeur de marché du bien, ne
dépend que des prix d'offre individuelle, loin des influences.
De même, la théorie des jeux démontre sous les mêmes hypothèses que :
— L'enchère hollandaise N°4 et l'enchère scellée au premier prix N°1 sont
équivalentes du point de vue informationnel — et que — L'enchère anglaise
N°3 et l'enchère scellée au second prix N°2 sont également équivalentes.
Dans ce modèle totalement symétrique, les quatre procédures d'enchères
assurent une allocation Pareto-optimale, un équilible qu’aucune autre
situation ne surpasse : le bien est attribué à celui qui en fera l'utilisation la
plus efficace et qui le valorise le plus.
Et les mathématiciens déduisent que le revenu espéré du vendeur est une
fonction croissante du nombre d'enchérisseurs.
The revenue equivalence theorem states that any allocation
mechanism/auction will lead to the same expected revenue for the seller
and optimal for players.
But this indifference in chosing one of the main four system is only theorical
as it implies four strong assumptions :
— the bidder with the highest valuation always wins
— the bidder with the lowest possible signal expects zero surplus
— all bidders are risk neutral, and
— all bidders are drawn from a strictly increasing and atomless distribution
Relaxing these assumptions can provide valuable insights for auction
design. Decision biases can also lead to predictable non-equivalencies.
Additionally, if some bidders are known to have a higher valuation for the
lot, techniques such as price-discriminating against such bidders will yield
higher returns. In other words, if a bidder is known to value the lot more
than the next highest bidder, the seller can increase their profits by charging
that bidder. He will still win the lot, but will pay more.
The linkage principle is a finding which states that auction houses have an
incentive to pre-commit to revealing all available information about each
lot, positive or negative.
The linkage principle is seen in the art market with the age-old tradition of
auctioneers hiring art experts to examine each lot and pre-commit to
provide a truthful estimate of its value.
a few auctions in Brussels in April and June
Littérature, musique, photographie
descriptions : Devroe & Stubbe
The Romantic Agony
a few auctions in Brussels in April and June
April 24
April 25
friday 24th + saturday 25th april at 1 pm
40 rue de l’Aqueduc - Bruxelles
http://www.romanticagony.com/en/catalogue
DOCUMENTARY PHOTOGRAPHS
Photographies documentaires
Descriptions : Rhinoceros & Cie
The Romantic Agony
June 19
friday 19th + saturday 20th June at 2 pm
40 rue de l’Aqueduc - Bruxelles
Daguerreotypes, Calotypes, Photolithographs, Autochroms, Art history documentation.
Remarkable portrait of Paul Gauguin & Vincent van Gogh.
Catalogue in progress, should be online in early May
June 20
The covers you have missed
The covers you have missed
Transmission
Transmission
13-2015
13-2015
He becomes an auctioneer
Buyer’s Remorse
n°108
uploaded at 3.15 pm
monday 30th march 2015
n°109
uploaded at 3.15 pm
monday 30th march 2015