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  • Imaras

    Bidding with Imaras

    Imaras is a multi-attribute auction system. It allows for bidding two or more attributes (e.g. price, lead time and warranty). The system supports several types of settings, including:

    1. Hosting by the auction owner (buyer or seller), an intermediary, or a market maker.
    2. Disclosure of bids to bidders: only bidder’s own bid is displayed, both own and winning bids are displayed, or all bids are displayed.
    3. Bidding process: continuous (asynchronous bidding) or round-based (synchronous bidding); rounds may take minutes, hours or days.

    The key elements of the Imaras process are illustrated with a round-based auction set by a buyer who wants to purchase a product described by three attributes.

    One of the key features of the Imaras auction is that the auctioneer (buyer) does not provide the bidders (sellers) with explicit set of preferences. The information that is given to the bidders is of the same type as it is given in a single attribute auction (price). That is, they obtain only information about the preferred direction for each attribute (e.g., price not higher than $230, lead time not longer than 24 days, and warranty not shorter than 30 months). This information provided by Imaras is called limits.

    In the round-based auction Imaras calculates limits at the beginning of each round. There may be one or more sets of limits; a set comprises limits determined for each attribute. The limits for one round are calculated based on the winning bid made in the previous round and parameters set up by the buyer.

    Knowledge of the current limits (i.e., displayed at the beginning of each round) is sufficient to make bids. Allowable bid is one that conforms to at least one of the limit sets. The auction will close if one of the following conditions is met:

    1. No more than one bidders bid in a round;
    2. The closing time is reached.

     Example of bidding using limit sets

    The limits are formulated for every attribute. There may be a few or several limit sets. For example, if there are three attributes: price (P); lead time (L) and warranty (W), in round 1, Imaras may construct the following three limit sets:
      Set11 = {P ≤ $150; L ≤ 60 days; W ≥ 36 months);
      Set21 = {P ≤ $160; L ≤ 63 days; W ≥ 39 months); and
      Set31 = {P ≤ $143; L ≤ 56 days; W ≥ 37 months).

    If a bidder wants to make a bid, then she has to observe the limits. This means that the every bid has to follow the limits formulated in one of the three sets. The bidder cannot choose one limit from one set and another limit—from another set.

    Let’s assume that the following two bids were made in round 1:
      Bid1 = ($158; 62 days; 40 months)         and       Bid2 = ($141; 54 days; 37 months).

    After the bidders submit their bids, Imaras updates the limit sets taking the bids into account. Hence, in round 2, Imaras may provide the bidders with the following two sets:
      Set12 = {P ≤ $155; L ≤ 63 days; W ≥ 39 months); and
      Set22 = {P ≤ $140; L ≤ 57 days; W ≥ 36 months).

    The bidders now make their bids observing the limits given in these two sets. If the only bid made is:
       Bid3 = ($149; 63 days; 40 months),
    then this bid is the winning bid.