Databases Reference
In-Depth Information
If the second object is going to simultaneously occur with the first object,
then any incremental expense or opportunity missed to cause the second
object to occur is unnecessary. Instead, the enterprise should expend its
resources to make the first object occur, and then let the second object
occur simultaneously with the first object. In other words, if it's good, and
it will happen, let it happen.
If, however, the simultaneous occurrence of the two objects in an
Itemset is disadvantageous to the enterprise, the enterprise is equipped
with the knowledge that a disadvantageous scenario has a strong tendency
to occur. The enterprise can then choose to either prevent the simulta-
neous occurrence of objects or leverage the simultaneous occurrence of
objects. If the enterprise is able to prevent the second object from occur-
ring, but at an incremental cost, then the enterprise can choose to either
expend the resources necessary to prevent the second object from occur-
ring simultaneously with the first object or the enterprise can choose to
absorb the simultaneous occurrence of the second object. The question is,
Which has the higher cost, the prevention or the problem? Problems do
exist that cost more than their prevention. So, in the case of a disadvanta-
geous Complement, an action can be to either tolerate the co-occurrence
of the objects in an Itemset or prevent the co-occurrence of the objects in
an Itemset.
Another action to be taken in the case of a disadvantageous Complement
is to leverage one of the two objects. An example of the leverage of a dis-
advantageous Complement is a tariff, that is, a tax on imported products.
A tariff is levied on imported products to increase the price of those prod-
ucts when they sell in a retail store. In this situation, the two objects are
(1) imported products and (2) reduced sales of domestic products and the
Itemset is a fiscal period (e.g., fiscal quarter, fiscal year), which is measured
by the GDP of the fiscal period. The disadvantageous Complement is
caused when an imported, rather than domestic, product sells in the retail
market. The domestic government prefers that domestic products sell as
much as possible. A tariff works to prevent the presence of imported prod-
uct in retail stores, which is expected to cause the sale of domestic prod-
ucts to increase. The use of a tariff also has the added benefit of increasing
the revenues of the domestic government.
In an enterprise disadvantageous Complements will occur. If the dis-
advantageous Complement cannot be prevented, and the cost is intoler-
ably high, then it should be leveraged. Like the tariff, the enterprise can
respond to the disadvantageous Complement by modifying the situation
