In the query planning service example above, we have made some assumptions about what it means in the taxonomy for the topic Science to be more general than Astronomy in a market context. However, there are a number of different ways in which we could interpret this taxonomy.
Consider the difference between a Science query planning service that is composed of bundled Astronomy and biology query planners and one that makes undifferentiated queries across any and all Science sources. We can describe the bundled () technology as one that can be easily decomposed, or unbundled, into several subparts whereas an undifferentiated () technology cannot. Next, assuming that Science can be unbundled into separate Astronomy and Biology query planners, is it the buyer or seller who chooses which service will be used? We describe buyer's choice using the operator and seller's choice with .
These four logical operators on market descriptions are shown below:
Operator | Example | Meaning |
[class c] | [Science] | Buyer's choice of |
subclasses of Science | ||
[class c] | [Science] | Seller's choice of |
subclasses of Science | ||
[class c] | [Science] | Bundled subclasses |
of Science | ||
[class c] | [Science] | Undifferentiated |
Science |
Service | Trade | 3c|Query Planning Service Attributes | ||
Market | Context | 3c| | ||
# | Audience | Topic | Recommending-Org | |
1 | buy, sell | High School | [Astronomy] | unspecified |
2 | buy | High School | [Astronomy] | Astronomy Today |
3 | buy | [School] | [Astronomy] | unspecified |
4 | sell | High School | [Science] | unspecified |
5 | sell | [School] | Black Holes | unspecified |
6 | sell | unspecified | [Astronomy] | unspecified |
In the case of query planning services, it seems unlikely that a buyer is going to want to let the seller choose the topic (i.e., seller's choice). Indeed, within the UMDL, we make the default assumption that all query planning services are buyer's choice, considerably simplifying the search for related markets.
However, for other goods seller's choice is a reasonable operator. Consider a newspaper subscription--subscribers don't choose the articles that appear in each day's paper. In a buyer's choice article market, buyers would pick and choose among available articles, essentially creating their own customized paper. Each of these two choice operators composes individual articles into a different, more abstract, bundled article market.
The idea of bundled goods is far from new, and has been generally addressed in economic literature as an alternative technique for price discrimination [17]. By reducing the dispersion in consumer tastes across different bundles a seller can often extract more value from transactions than uniform pricing would. Although historically goods have often been unprofitable to bundle, in the case of information goods and services (with marginal costs close to zero) selling bundled goods can yield higher profits and greater efficiency than selling them separately [3]. One ongoing field trial in this area includes the PEAK project, offering Elsevier journal articles with different experimental bundles and prices [13].
What we introduce here is the ability of the buyer or seller to choose a sub-bundle of the bundled goods, as defined in Table 2. These are not the only possible ways of choosing sub-bundles; the set of market operators could be extended.
Operator
Definition
Bundle
Example
Buyer's
Choice
Buyer chooses one of
Example
Buyer chooses one of
Seller's
Choice
Seller chooses one of
Example
Seller chooses one of
In the next section, we describe how to use this notation for automatic matching of buyers and sellers to markets.