Objectives: Introduction Over View of System Analysis and Design
Identify data used and information produced
Download 0.94 Mb. View original pdf
|
- Navigate this page:
- 6.2.5 Determine process timing and volume
| 6.2.4 Identify data used and information produced Analysts next need to find out what data are used to perform each activity for example, to reorder inventory, the buyer might require data describing the quantity of an item of hand, expected demand for the item, supplier name, and item cost. To know when to place an order, the buyer would also consider the necessary lead-time (how for in advance the item should be ordered to be on hand when needed. Most business transactions also produce information that is useful to managers when they evaluate employee, business, and systems performance and that maybe useful in another context to both manager and analyst. Inquiring analysts will find out, for example that data about inventory reordering and stocking also provide information about warehouse demands, purchasing practices, sales, and cash flow. 6.2.5 Determine process timing and volume The frequency of business activities varies greatly. For example, some activities, such as paying taxes, occur only a few times a year, whereas paying employees is a weekly activity. Therefore, analysts should learn how often the activity is repeated. Knowing whether an activity occurs frequently may lead the analyst to raise many additional and important questions to determine the reason for the frequency and its effect on business activities. Many times the easiest way to get this information is to identify the reason for the activity what causes the activity to be performed Analysts sometimes refer to the direct cause as the trigger function. (it triggers the activity) Activities can be triggered by customers of an application to open anew bank, charge, or credit account, and by the passage of time (the ending of the day, week, or month. Unless analysts know what triggers an activity, they may misunderstand the reason for the activity and give it more or less importance in the system than it merits. Some activities, such as completing a purchase requisition, take only a few seconds. Others, such as deciding whether to accept a merger offer, occur infrequently but require a great deal of time when they do take place. Timing alone does not determine the importance of an activity, but it does affect the way analysts evaluate certain steps in carrying out the performance. For example, making a telephone call to obtain stock price information during a merger decision is quite acceptable, since a merge is an infrequent occurrence. But making a telephone call to obtain information every time a purchase requisition is processed is another matter. The volume of items to be handled may increase the amount of time needed to complete the activity. Savings banks prepare consumer account statements (summaries of deposits, withdrawals, interest accumulations, and balances) only four times a year. Although the frequency of this activity is very low, when the calendar triggers this activity at the end of each quarter, the volume of work is very high, sometimes running into tens of thousands of statements to be prepared. The sheer quantity of item making up an activity can produce special problems for the analyst to study, even though the activity occurs infrequently. |