In this chapter you will learn: How can information systems be used to support teams of workers? How many different ways are there to communicate with team members? Which method is best for each type of message? How can several people work on the same documents?,...
Trang 1Copyright © 1998-2002 by Jerry Post
Introduction to MIS
Chapter 8 Models and Decision Support
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1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Actual Forecast
Trang 3Outline
Trang 4Decision Levels
Business Operations
Tactical Management
Strategic Mgt.
EIS
ES
T
action
P
ssing
trolModels
Trang 5Choose a Stock
Stock Price
90 95 100 105 110 115 120 125 130
1 2 3 4 5 6 7 8 9 10 11 12
Month
CompanyA CompanyB
Company A’s share price increased by 2% per month
Company B’s share price was flat for 5 months and then increased by
3% per month
Which company would you invest in?
Trang 6 Heuristics: Rules of thumb
Anchoring and adjustment
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10 1 3
5 0
5 10 15 20 25
File: C08Fig08.xls
Why Build Models?
Trang 80 5 10 15 20 25
Economic/
regression Forecast
File: C08Fig09.xls
Trang 90 5 10 15 20 25
Trang 10Object-Oriented Simulation Models
Customer
purchase order
Order Entry
Custom Manufacturing
purchase order
Shipping Schedule
Invoice
Trang 11DSS: Decision Support Systems
sales revenue profit prior
Sales and Revenue 1994
Jan Feb Mar Apr May Jun 0
50 100 150 200 250 300 Legend Sales Revenue Profit Prior
results
File: C08Fig11.xls
Trang 12Data Mining: Spotfire
http://www.spotfire.com
Trang 13Data Warehouse
OLTP Database3NF tables
Operations
data
Predefinedreports
Data warehouseStar configuration
Daily datatransfer
Interactivedata analysis
Flat files
Trang 14Multidimensional OLAP Cube
Time
CustomerLocation
Cate
gory
Pet StoreItem SalesAmount = Quantity*Sale Price
Trang 15Microsoft SQL Server Cube Browser
Trang 16Microsoft Pivot Table
Trang 17Plant schedule
Trang 18EIS: Executive Information System
Trang 19Executive IS
ProductionDistribution
Production Costs
SouthNorthOverseas
0 500 1000 1500 2500 3000 4000 4500
1993 1994 1995 1996
South North Overseas
Trang 20Marketing Research Data
Trang 21Marketing Sales Forecast
GDP and Sales
1000 1200 1400 1600 1800 2000 2200 2400 2600 2800
GDP Sales Forecast
forecast
Note the fourth quarter sales jump
The forecast should pick up this cycle.
File: C08-10 Marketing Forecast.xls
Trang 22Regression Forecasting
Sales = b0 + b1 Time + b2 GDP Model:
Forecast GDP for each quarter.
Trang 23Human Resources
File: C08-19 HRM.xls
Trang 240 500
Trang 25Finance Example: Project NPV
P ro je c t C N P V = $ 3 , 8 14
-100,000 -80,000 -60,000 -40,000 -20,000 0 20,000 40,000 60,000
Ye a r
Costs-C Revenue-C
Rate = 7%
Can you look at these cost and revenue flows and tell if the project should be accepted?
File: C08-14 Finance NPV.xls
Trang 26Balance Sheet for 2003
Total Current Assets 136,886 Total Current Liabilities 98,963
File: C08-15 Accounting.xls
Trang 27Income Statement for 2003
Earnings before interest & tax 21,125 shares out 9763
Add to Retained Earnings 4,097
Earnings per share $0.42
Trang 28Balance Sheet projected 2004
Income Statement projected 2004
Forecast sales and costs.
Forecast cash, accts receivable, accts payable, accruals.
Add gain in retained earnings.
Compute funds needed and interest cost.
Add new interest to income statement.
4
2
3
5 Total Cur Assets 150,576
Trang 30Blue 1.9
Green 2.3
Red
1.7 Yellow
1.1
Blue 1.0
Green 1.1
Red
2.1 Yellow
1.7
Blue 1.1
Green 1.4
Blue 3.2
Green 3.7
Red
1.8 Yellow
1.5
Blue 1.2
Green 1.4
Red
2.6 Yellow
3.0
Blue 1.9
Green
1.6
Red
3.6 Yellow
3.8
Blue 3.2
Green 2.9
Red
3.5 Yellow
3.8
Blue 2.5
Green 2.0
Red
1.4 Yellow
2.0
Blue 2.1
Green 1.7
Hard
Goods
1990 Soft Goods
Trang 31Cases: Computer Hardware Industry
Trang 32Cases: Dell Computer
Gateway 2000, Inc.
What is the company’s current status?
What is the Internet strategy?
How does the company use information technology?
What are the prospects for the industry?
www.dell.com
www.gateway.com
Trang 33Appendix: Forecasting Uses
Trang 34trend
Trang 35Structural Equations
QD = b0 + b1 Price + b2 Income + b3 Substitute
QD = 1114 - 0.1 Price + 1.2 Income - 1.0 Substitute
Model
EstimateData
Forecast 33318 = 1114 - 0.1 (155) + 1.2 (20000) - 1.0 (160)
Need to know (estimate) future price, income, and substitute price
Trang 36Time Series Components
A cycle is similar to the seasonal pattern,but covers a time period longer than a year
Trang 37St = Yt + (1 - ) St-1
S is the new data point
is the smoothing factor
Use Excel:
Tools, Data AnalysisExponential Smoothing
Trang 38Exponential Smoothing
Choosing the smoothing factor ( ):
It is usually between 0.01 and 0.20
Test multiple values and compare errors:
(actual - smooth) * (actual - smooth)
Compute the sum Choose the factor with
the least total sum-of-squared error
(A2-D2)*(A2-D2)
Larger factors placemore importance onrecent data, which results in less
smoothing
Trang 39Smoothing with Trends
Double Exponential Smoothing
20000 22000 24000 26000 28000 30000 32000 34000
1 3 5 7 9 11 13 15 17 19
Raw Data Smooth:0.20
Apply exponential smoothing and choose smoothing factor ( )
Apply exponential smoothing a second time to the smoothed data
Trang 40Forecasting with Exponential Smoothing
Forecast for time T+
] 2
[
1
1 1
S20 = 32,064 (value at time 20, after one smoothing)
S[2] = 33,141 (value at time 20, after second smoothing)
Y21 = (2.25)32,064 - (1.25)33,141
= 30,718
Trang 41Moving average captures all
elements, but lags the actual pattern.
Trang 42Regression Analysis
=$F$20+$F$21*B6
Tools + Data Analysis + Regression Dependent = Sales
Independent = Time
Trang 43Estimating Trend
Yt = b0 + b1(t)
Use regression to estimate b0 and b1
Plug t into equation to estimate new value (on trend):