Page 281 - Socially Intelligent Agents Creating Relationships with Computers and Robots

264 Socially Intelligent Agents

Auction Scene DIALOGIC
FRAMEWORK
ONTOLOGY (O)
e-auctions
LANGUAGE (L)
FOL ROLES (R)
CL 0 10
ACL
min
PARTICLES (I) a
a a Max
b b commit
inform
6 request min
11 question b
refuse Max
w 0 w f1 ω 8 ω 7
8
9
ω 9 LABEL LIST ( λ )
10
13
2. inform(!x:a,all:b,open_round(?r))
1 13 12 6 1. inform(?x:a,all:b,open_auction(!n))
ω 10
3. inform(!x:a,all:b,to_sell(?good_id))
5
4. inform(!x:a,all:b,buyers(?b1,...,?bn))
5
ω 11 5. inform(!x:a,all:b,offer(!good_id,?price))
6. commit(?y:b,!x:a,bid(!good_id,!price))
5
7. inform(!x:a,all:b,withdrawn(!good_id,!price))
2 3 4 5 8. inform(!x:a,all:b,collision(!price))
ω 1 ω 2 ω 3 ω 4 ω 5 9. inform(!x:a,all:b,sanction(?buyer_id))
10. inform(!x:a,all:b,expulsion(?buyer_id))
7 5 11. inform(!x:a,all:b,sold(!good_id,!price,?buyer_id)
12
b 12. inform(!x:a,all:b,end_round(!r))
13. inform(!x:a,all:b,end_auction(!n,?reason))
ω 6
Figure 32.1. Graphical Specification of an Auction Scene
One of the fundamental tasks of interagents is to ensure the legal exchange
of illocutions among the agents taking part in some scene: what can be said,
to whom and when. For this purpose, interagents employ conversation proto-
cols (CP) [4]. CPs define coordination patterns that constrain the sequencing
of illocutions within a scene and allow to store, and subsequently retrieve,
the contextual information (illocutions previously sent or heard) of ongoing
scenes. We can think of CPs as scenes extended with the necessary actions to
keep contextual information. Based on contextual information, when receiving
some illocution from an external agent to be transmitted, an interagent can as-
sess whether the illocution is legal or else whether it must be rejected or some
enforcement rule activated.
Consider the auction scene. A buyer agent receives the prices called by
the auctioneer through his interagent, which keeps track of the latest price
called. When the buyer agent submits a bid, his interagent collects it and
verifies whether the buyer is bidding for the latest offer price. If so, the in-
teragent posts the bid to the auctioneer, otherwise it’s rejected. Once the bid
has been submitted, the buyer is not allowed to re-bid. If he tries, their bids are
disallowed, and if he compulsively tries his interagent unplugs him from the
institution. Then his interagent autonomously follow the required procedures
to log the buyer out from the auction house.
Interagents also constrain external agents’ behaviour in their transition be-
tween scenes. Figure 32.2 depicts the specification of the performative struc-