IS-171
Computing With
Spreadsheets
Decision Making
Week 4
Decision Making


Quality of decisions
Ways Excel helps
5/29/2016
Carol Wilson and Fred Ferwerda
2
Garbage In, Garbage Out

5/29/2016
Tale of James A. Cummings Inc.
Input
Processing
Output
Bad
Whatever
Bad
Good
Bad
Bad
Good
Good
Good
Carol Wilson and Fred Ferwerda
3
Making Quality Decisions


Excel is only a tool.
Double check




Input
Processing
Good formatting helps
Then and only then use the spreadsheet for
decision making.
5/29/2016
Carol Wilson and Fred Ferwerda
4
Ways Excel helps


Functions (instead of simple formulas)
Built in commands



5/29/2016
Goal Seek
Scenario Manager (Chapter 6)
Solver (Appendix B)
Carol Wilson and Fred Ferwerda
5
Functions

Predefined formulas



Examples



Take arguments (parameters) as input
Return some calculated value as output.
Sum
Average
Writing a function



5/29/2016
Insert Function
fx Icon
Just type
Carol Wilson and Fred Ferwerda
6
Functions Continued



In conjunction with cell ranges, allow
addition/deletion of rows/columns
Logic functions allow rudimentary
programming
Useful



5/29/2016
Predefined: PMT is hard to write
Smart: auto add inserted column/row
Flexible: IF allows conditional behavior
Carol Wilson and Fred Ferwerda
7
Many functions available







Math
Finance
Date
Text
Database
Statistical
Logical
5/29/2016
Abs, Log, Rand, Round, Sum
FV, PV, Pmt
Today, Now, Minute
Find, Substitute, Trim, Upper
DAverage, DCount, DMin
Average, Rank, Stdev
If, And, Or, Not
Carol Wilson and Fred Ferwerda
8
IF

If condition



Example


Then Value1
Else Value2
=IF(A1>60, “Pass”, “Fail”)
Nesting Example

5/29/2016
=IF(A1>85, “Good”, IF(A1>60, “Okay”, “Fail”))
Carol Wilson and Fred Ferwerda
9
VLookup


Looks up a value from a sorted table
Parameters




Value to look up
Table reference
Column number
=VLOOKUP(I4, $I$20:$J$24, 2)
5/29/2016
Carol Wilson and Fred Ferwerda
10
PMT and FV

PMT: Periodic Payments




Interest rate
Number of payments
Present value (negative for loans)
FV: Future value of an investment



5/29/2016
Interest rate
Number of payments
Payment made each period (negative value)
Carol Wilson and Fred Ferwerda
11
Built-in Commands





Hide
Freeze panes
AutoFilter
Sort
Goal Seek
5/29/2016
Carol Wilson and Fred Ferwerda
12