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Chapter 4
Event Sequences
Events are listed on
the matrix in value
chain sequence
Look back at the event rows on the matrix in Figure 4-6 and you will notice that
events are not listed alphabetically. Instead, they are listed in value sequence begin-
ning with MANUFACTURING PLANS, and ending with WAREHOUSE
SHIPMENTS. This sequence orders the events by the increasing value of their
outputs. In this example, the sequence starts with potentially valuable planning
followed by the procurement of lower value components, and proceeds through
the building and shipment of higher value products. When business activity is
ordered in this way it is often referred to as a value chain.
Time/Value Sequence
Value sequence can
also represent time
sequence which
helps stakeholders
to think of the next
and previous events
Value sequence can also represent time sequence. Generally low value output
activity occurs before high value output activity or at least that is how most of us
think of business activity at a macro-level. For example, in manufacturing, pro-
curement happens before product assembly, shipping, and sales. Similarly, in
service industries, time and money is spent acquiring low value (high cost) pros-
pects before converting them into potentially valuable customers and then into
high value (low cost) repeat customers. In reality, value sequencing may not be a
strict chronology because many of the micro-level business events described in a
value chain occur simultaneously and asynchronously—not waiting for one an-
other. However, time/value sequencing is highly intuitive and by documenting
events in this way, the matrix helps stakeholders to think of next or previous events,
and spot gaps (missing links) in their value chains.
Add events to an event matrix in the order in which they increase business value
by asking “Who does what next that adds value?”
Process Sequence
Events that occur in
a strict sequence
often represent
process milestones
Milestone events
are indented
beneath the event
that triggers them.
A
* degenerate
dimension creator
often indicates the
start of a process
sequence
Within the flexible chronology of value chains there will be stricter chronological
sequences of events that must occur sequentially to complete a significant time
consuming process such as order fulfillment or insurance claim settlement. These
process sequences—which begin with a process (initiating) event and continue
serially through a number of milestone events—are denoted on an event matrix by
indentation.
Figure 4-6 shows a process sequence of PURCHASE ORDERS to SUPPLIER
PAYMENTS. This documents that a delivery only occurs after a purchase order
(PO) has been processed and a payment is only made after a delivery has been
received. Notice that these events share a conformed PO dimension. This may only
be a degenerate PO NUMBER dimension in each event table but it ties these events
together at the atomic detail level and allows stakeholders to track the progress of
each PO item through delivery and payment. Notice also that POs are created by
PURCHASE ORDER events (denoted by a * on the matrix): PO numbers are
generated when an employee raises a purchase order. This confirms the strict