1. Process Analysis I: Flow Charts, Decision Tables, Decision Trees
Yale Braunstein
School of Information Management & Systems

2. Processes These lectures all relate to processes:
Describing, analyzing, developing, modifying, documenting,…
Types of processes include:
Decision processes
Data flow & manipulation processes, …
Specific approaches depend on internal needs & practices, standards

3. Flow charts There are several standards – just be consistent
Manual methods vs. automated tools
Visio, PowerPoint, etc.
Waves of fashion / variety of uses
Programming
Documenting processes
Multi-user settings
General documentation of all sorts

4. Flow chart techniques Basic symbols Terminator Process Decision
Predefined process
On-page connector
Connector

5. Flowchart guidelines Top to bottom, left to right on the page
Activity being flowcharted should be defined carefully and made clear to reader
Identity start and end
Use “one-verb” (verb-noun) descriptions
Examples: “prepare statement,” “file record”
Keep steps in proper sequence
Observe scope & range of activity; branches should be on separate pages
Use standard symbols; lines should NOT cross
Use cross-overs only if necessary; keep lines straight
No blind alleys or endless loops

6. Samples (with comments)
Dining room table (again)
Only partially complete, has potentially endless loop
Still partially complete, but with additional steps
Flow of logic in an SPSS session
No terminators, no decision points
Flow of information in a survey
No terminators, no decision points, but clear distinction betweens types of processes
How to obtain your FBI file (or Elvis’s)

7. Common problems Distinguish between “do it” and “schedule it”
Avoid endless loops
Account for & follow-up on holds / pauses / “unable to process” conditions, etc.
Make clear whether data flows and telecom links are one-way or two-way
Do NOT link to processes – use connectors

8. Other uses for Visio Document spreadsheets
Functional decomposition diagrams
Network & wiring diagrams
E-R diagrams for databases
Organization charts
Statistical documentation & output
Crime scene documentation, etc.
Links to some of these are on the course download page

9. Decision tables & Decision trees
Sometimes DFDs and E-R diagrams do not work adequately or the nature of the problem is more “analytic”
First, a slight digression: It may help to specify the underlying logic in “structured English”
Structured programming + natural English = Structured English

10. Examples of Structured English - 1
For each customer number in the customer table
For each loan in the loans table that matches the above customer number
Keep a running total of loans
Keep a running total of the original loan principal
Keep a running total of the current loan balance
Keep a running total of the amounts past due

11. Examples of Structured English - 2
Sequence of Actions approach:
Action 1: Go to inventory area
Action 2: present ID to guard
Action 3: Pick items from stock
Action 4: Wand the items

12. Action Conditions can be simple or complex
Simple Condition Actions:
If item is on shelf
Then sequence of actions
Else sequence of actions
Complex Condition Actions
Do the following based on the customer order
Case 1: Construct turkey sandwich
Case 2: Assemble taco salad
Case 3: Construct pastrami sandwich

13. Decision tables
May be a better alternative to characterize the actions taken in a given task
Tabular form of presentation that specifies a set of conditions and their corresponding actions
Sometimes used for guidance in decision-making, especially if trying to routinize a process.

14. Example: Should we cash the check?
Awful pun may go here
We can document the process with a flow chart or with a decision table (or both)
Which one is better?
Depends on common practice in organization
May depend on the specifics of the process
The policy (decision rule):
“A customer with check-cashing privileges is entitled to cash personal checks up to $75 and payroll checks from pre-approved local employers.”

15. Construction of the decision table
Four main parts:
Conditions vs. Actions
Stub vs. Entry
Conditions: think of a series of if statements
Actions: think of a series of then statements

16. General format

17. The “cash a check” table

18. Decision trees
A decision tree is an alternate approach to representing decision situation
More graphical
Easier to change (sometimes)
Shows conceptually what is going on—you step through the decision-making process
Legend:
Salaried?
Hours worked < 40?
Hours worked = 40?