CMPG 312
SU 1
DECISION SUPPORT SYSTEMS
BESLUITNEMINGSONDERSTEUNING
STELSELS
Uitkomste
Outcomes
Aan die einde van hierdie leereenheid behoort u:
At the end of this study unit: you should:
•Te weet waarom u hierdie module (CPMG312) doen as deel •Know why you are doing this module (CPMG312) as part of
van die program wat u gekies het,
the program that you have chosen
•Die begrippe kwantitatiewe analise en besluitsteunstelsels •Be able to explain the concepts of “quantitative analysis” and
te kan verduidelik,
“decision support systems”
•Model- en data-geöriënteerde besluitsteunstelsels te kan
•Be able to distinguish model- and data-oriented decision
onderskei,
support systems
•Die kwantitatiewe analise benadering te ken en elke fase
•Know the quantitative analysis approach and be able to
daarvan te kan verduidelik,
explain every phase of it
•Te weet hoe om ‘n kwantitatiewe analise model te
•Know how to develop a quantitative analysis model
ontwikkel,
•Be able to explain the advantages of mathematical modelling
•Die voordele van wiskundige modellering met insig te kan
with insight
verduidelik,
•Be able to explain the problems of the quantitative analysis
•Die probleme van die kwantitatiewe analise benadering met approach with insight.
insig te kan verduidelik.
Hoofstukoorsig
Chapter Outline
1.1
Wat is Kwantitatiewe Analise?
1.1
What Is Quantitative Analysis?
1.2
Besigheidsanalise
1.2
Business Analytics
1.3
Die Kwantitatiewe Analise-benadering
1.3
The Quantitative Analysis Approach
1.4
Hoe om 'n Kwantitatiewe Analise-model te 1.4
ontwikkel
How to Develop a Quantitative Analysis
Model
1.5
Die Rol van Rekenaars en Sigbladmodelle
in die Kwantitatiewe Analise-benadering
1.5
1.6
Moontlike Probleme in die Kwantitatiewe
Analise-benadering
The Role of Computers and Spreadsheet
Models in the Quantitative Analysis
Approach
1.6
Possible Problems in the Quantitative
Analysis Approach
1.7
Implementation — Not Just the Final Step
1.7
Implementering - nie net die finale stap
Inleiding
Introduction
Wiskundige gereedskap is vir duisende jare gebruik • Mathematical tools have been used for thousands
of years
Kwantitatiewe analise kan op 'n wye
•
•
verskeidenheid probleme toegepas word
§
§
§
Dit is nie genoeg om net die wiskunde van 'n
tegniek te ken nie
Dit is belangrik om die spesifieke
toepaslikheid van die tegniek te verstaan,
asook sy beperkings en aanames
Suksesvolle gebruik van kwantitatiewe
tegnieke lei gewoonlik tot 'n oplossing wat
tydig, akkuraat, buigsame, ekonomies,
betroubaar, en maklik om te verstaan en te
gebruik is.
• Quantitative analysis can be applied to a wide
variety of problems
§
Not enough to just know the mathematics of a
technique
§
Must understand the specific applicability of
the technique, its limitations, and assumptions
§
Successful use of quantitative techniques
usually results in a solution that is timely,
accurate, flexible, economical, reliable, and
easy to understand and use
Wat is ‘n “Quant?”
“Quant”
What is a
Wat is Kwantitatiewe Analise?
What is Quantitative Analysis?
•
Kwantitatiewe analise is 'n wetenskaplike
benadering tot bestuursbesluitneming waarin rou
data verwerk en gemanipuleer word om
betekenisvolle inligting te produseer.
Quantitative analysis is a scientific approach to
managerial decision making in which raw data are
processed and manipulated to produce meaningful
information
Wat is Kwantitatiewe Analise?
What is Quantitative Analysis?
• Kwantitatiewe faktore is data wat akkuraat bereken kan
word.
• Quantitative factors are data that can be accurately
calculated
o Verskillende beleggingsalternatiewe
o Rentekoerse
o Finansiële verhoudings
o Kontantvloei en opbrengskoerse
o Vloei van materiaal deur 'n voorsieningsketting
• Kwalitatiewe faktore is moeiliker om te kwantifiseer,
maar het 'n impak op die besluitnemingsproses.
o Different investment alternatives
o Interest rates
o Financial ratios
o Cash flows and rates of return
o Flow of materials through a supply chain
• Qualitative factors are more difficult to quantify but
affect the decision process
o
o
o
o
Die weer
Staats- en federale wetgewing
Tegnologiese deurbraak
Die uitkoms van 'n verkiesing
o
o
o
o
The weather
State and federal legislation
Technological breakthroughs
The outcome of an election
Wat is Kwantitatiewe Analise?
What is Quantitative Analysis?
• Kwantitatiewe en kwalitatiewe faktore kan verskillende
rolle hê.
• Quantitative and qualitative factors may have different
roles
• Besluite gebaseer op kwantitatiewe data kan
geoutomatiseer word.
• Decisions based on quantitative data can be
automated
• Kwantitatiewe analise sal oor die algemeen die
besluitnemingsproses ondersteun.
• Generally quantitative analysis will aid the decisionmaking process
• Dit is belangrik in baie areas van bestuur.
• Important in many areas of management
o Produksie/Operasionele Bestuur
o Voorsieningskettingbestuur
o Production/Operations Management
o Supply Chain Management
o Besigheidsanalise.
o Business Analytics
Besigheidsanalise
• 'n Data-gedrewe benadering tot besluitneming
Business Analytics
• A data-driven approach to decision making
o
Maak beter besluite moontlik
o
Allows better decisions
o
o
Groot hoeveelhede data
o
o
Large amounts of data
o
Statistiese en kwantitatiewe analise word gebruik
om die data te ontleed en nuttige inligting te
verskaf.
o
Statistical and quantitative analysis are used to
analyze the data and provide useful information
Inligtingstegnologie is baie belangrik
Information technology is very important
Besigheidsanalise
Business Analytics
• Beskrywende analise - die studie en samevoeging van
historiese data
• Descriptive analytics – the study and consolidation of
historical data
• Voorspellende analise - die voorspelling van toekomstige
uitkomste gebaseer op patrone in die verlede data
• Predictive analytics – forecasting future outcomes
based on patterns in the past data
• Voorskriftelike analise - die gebruik van
optimaliseringsmetodes.
• Prescriptive analytics – the use of optimization
methods
Besigheidsanalise
Business Analytics
TABLE 1.1 Business Analytics and Quantitative
Analysis Models
Die Kwantitatiewe Analise-benadering
The Quantitative Analysis Approach
FIGURE 1.1 The
Quantitative Analysis
Approach
Definieër die Probleem
Defining the Problem
• Ontwikkel 'n duidelike en bondige verklaring van die
probleem om rigting en betekenis te bied.
o
o
o
o
Dit kan die belangrikste en moeilikste stap wees.
Gaan verder as simptome en identifiseer ware
oorsake.
Konsentreer op net 'n paar van die probleme - die
regte probleme kies is baie belangrik.
Spesifieke en meetbare doelwitte mag ontwikkel
moet word.
• Develop a clear and concise statement of the problem
to provide direction and meaning
o
o
This may be the most important and difficult step
o
Concentrate on only a few of the problems –
selecting the right problems is very important
o
Specific and measurable objectives may have to
be developed
Go beyond symptoms and identify true causes
Die ontwikkeling van 'n model
Developing a Model
• Modelle is realistiese, oplosbare en verstaanbare
wiskundige voorstellings van 'n situasie
•
• Verskillende tiepe modelle
•
Models are realistic, solvable, and understandable
mathematical representations of a situation
Different types of models
Verkryging van insetdata
Acquiring Input Data
• Insetdata moet akkuraat wees - GIGO-reël
• Data kan uit 'n verskeidenheid bronne afkomstig wees maatskappyverslae, dokumente, werknemeronderhoude, direkte meting, of statistiese
steekproefneming.
• Input data must be accurate – GIGO rule
• Data may come from a variety of sources – company
reports, documents, employee interviews, direct
measurement, or statistical sampling
Die ontwikkeling van 'n oplossing
Developing a Solution
• Die manipulasie van die model om by die beste
(optimale) oplossing uit te kom
• Manipulating the model to arrive at the best (optimal)
solution
• Gewone tegnieke sluit in:
o Die oplos van vergelykings
• Common techniques are
o Solving equations
o Probeer en tref - verskeie benaderings probeer en
die beste resultaat kies
o Trial and error – trying various approaches and
picking the best result
o Volledige telling - probeer alle moontlike waardes
o Complete enumeration – trying all possible
values
o Gebruik van 'n algoritme - 'n reeks herhalende
stappe om 'n oplossing te bereik.
o Using an algorithm – a series of repeating steps
to reach a solution
Toets die oplossing
Testing the Solution
• Beide insetdata en die model moet getoets word vir
akkuraatheid en volledigheid voor analise en
implementering
o Nuwe data kan ingesamel word om die model te
toets
o Resultate moet logies, konsekwent en die werklike
situasie verteenwoordig.
• Both input data and the model should be tested for
accuracy and completeness before analysis and
implementation
o
New data can be collected to test the model
o
Results should be logical, consistent, and
represent the real situation
Analiseer die resultate
Analyzing the Results
• Bepaal die implikasies van die oplossing
• Determine the implications of the solution
o
Die implementering van resultate vereis dikwels
verandering in 'n organisasie
o
Implementing results often requires change in an
organization
o
Die impak van aksies of veranderinge moet
bestudeer en verstaan word voor implementering
o
The impact of actions or changes needs to be
studied and understood before implementation
• Sensitiwiteitsanalise, ná-optimaliteitsanalise, bepaal
hoeveel die resultate sal verander as die model of
insetdata verander
o
Sensitiewe modelle moet baie deeglik getoets word
• Sensitivity analysis, post-optimality analysis,
determine how much the results will change if the
model or input data changes
o
Sensitive models should be very thoroughly
tested
Implementering van die resultate
Implementing the Results
• Implementering sluit die oplossing in by die maatskappy
• Implementation incorporates the solution into the
company
o
Implementering kan baie moeilik wees
o
Mense kan weerstand bied teen veranderinge
o
Implementation can be very difficult
o
Baie pogings van kwantitatiewe analise het misluk
omdat 'n goeie, werkende oplossing nie behoorlik
geïmplementeer is nie
o
People may be resistant to changes
o
Many quantitative analysis efforts have failed
because a good, workable solution was not
properly implemented
• Veranderinge gebeur oor tyd, sodat selfs suksesvolle
implementerings gemonitor moet word om te bepaal of
aanpassings nodig is.
• Changes occur over time, so even successful
implementations must be monitored to determine if
modifications are necessary
Hoe om 'n kwantitatiewe analise-model te ontwikkel
How to develop a Quantitative Analysis Model
n Wiskundige model van wins:
A mathematical model of profit:
Hoe om 'n kwantitatiewe analise-model te ontwikkel
How to develop a Quantitative Analysis Model
Inkomste en uitgawes kan op verskillende maniere uitgedruk word.
Revenue and expenses can be expressed in different ways
Hoe om 'n kwantitatiewe analise-model te ontwikkel
How to develop a Quantitative Analysis Model
Pritchett’s Precious Time Pieces
The company buys, sells, and repairs old clocks
• Rebuilt springs sell for $8 per unit
• Fixed cost of equipment to build springs is $1,000
• Variable cost for spring material is $3 per unit
Pritchett’s Precious Time Pieces
Companies are often interested in the break-even point (BEP), the BEP is
the number of units sold that will result in $0 profit
Fixed cost
BEP =
(Selling price per unit) - (Variable cost per unit)
Voordele van wiskundige modellering
Advantages of Mathematical Modeling
1.
Modelle kan werklikheid akkuraat verteenwoordig.
1.
Models can accurately represent reality.
2.
Modelle kan 'n besluitnemer help om probleme te
formuleer.
2.
Models can help a decision maker formulate
problems.
3.
Modelle kan insig en inligting bied.
3.
Models can give us insight and information.
4.
Modelle kan tyd en geld bespaar in die besluitneming
en probleemoplossing.
4.
Models can save time and money in decision
making and problem solving.
5.
'n Model kan die enigste manier wees om groot of
ingewikkelde probleme binne 'n tydige manier op te
los.
5.
A model may be the only way to solve large or
complex problems in a timely fashion.
6.
A model can be used to communicate problems and
solutions to others.
6.
'n Model kan gebruik word om probleme en oplossings
aan ander te kommunikeer.
Models Categorized by Risk
Modelle gekategoriseer volgens risiko
•
Wiskundige modelle wat nie risiko of kans behels nie,
•
word deterministiese modelle genoem
o Al die waardes wat in die model gebruik word, is met
volledige sekerheid bekend.
Mathematical models that do not involve risk or
chance are called deterministic models
o All of the values used in the model are known
with complete certainty
•
Wiskundige modelle wat risiko of kans behels, word
waarskynlikheidsmodelle genoem.
o Waardes wat in die model gebruik word, is skattings
gebaseer op waarskynlikhede.
Mathematical models that involve risk or chance are
called probabilistic models
o Values used in the model are estimates based on
probabilities
•
Rekenaars en sigbladmodelle
Computers and Spreadsheet Models
POM-QM for Windows
•An easy to use decision
support system for use
in POM and QM courses
•This is the main menu
of quantitative models
• An Excel add-in
PROGRAM 1.1 The QM for
Windows Main Menu
Rekenaars en sigbladmodelle
Computers and Spreadsheet Models
PROGRAM 1.3 Excel QM in Excel 2016 Ribbon and
Menu of Techniques
Rekenaars en sigbladmodelle
Computers and Spreadsheet Models
PROGRAM 1.4 Entering the Data for Pritchett’s Precious Time
Pieces Example into Excel QM in Excel 2016
Rekenaars en sigbladmodelle
Computers and Spreadsheet Models
PROGRAM 1.5 Using Goal Seek in the Break-Even Problem to
Achieve a Specified Profit
Moontlike probleme in die kwantitatiewe analisebenadering
Possible Problems in the Quantitative Analysis
Approach
• Definineër die probleem
o Probleme kan nie maklik geïdentifiseer word nie
o Teenstrydige standpunte
o Impak op ander departemente
o Aanvanklike aannames
o Oplossing verouderd
• Defining the problem
o Problems may not be easily identified
o Conflicting viewpoints
o Impact on other departments
o Beginning assumptions
o Solution outdated
• Ontwikkeling van 'n model
o Pas die handboekmodelle aan
o Verstaan die model nie
• Developing a model
o Fitting the textbook models
o Understanding the model
Moontlike probleme in die kwantitatiewe analisebenadering
Possible Problems in the Quantitative Analysis
Approach
• Verkryging van akkurate insetdata
• Acquiring accurate input data
§ Gebruik van rekeningkundige data
§ Using accounting data
§ Geldigheid van die data
• Ontwikkeling van 'n oplossing
§ Validity of the data
• Developing a solution
§ Moeilik verstaanbare wiskunde
§ Slegs een antwoord is beperkend
§ Hard-to-understand mathematics
§ Only one answer is limiting
• Toets die oplossing
• Testing the solution
§ Oplossings is nie altyd intuïtief voor die hand
liggend nie
• Analise van die resultate
§ Hoe sal dit die hele organisasie beïnvloed
§ Solutions not always intuitively obvious
• Analyzing the results
§ How will it affect the total organization
Implementering - Nie Net Die Finale Stap
Implementation – Not Just the Final Step
• Gebrek aan betrokkenheid en weerstand teen
verandering
o Vrees dat formele analiseprosesse die
besluitnemingsmag van die bestuur sal verminder
o Vrees dat vorige intuïtiewe besluite as ontoereikend
blootgestel sal word
o Ongemaklik met nuwe denkpatrone
o Managers wat aksiegerig is, mag "vinnige en
maklike" tegnieke wil hê
o Bestuursondersteuning en gebruikersbetrokkenheid
is belangrik.
• Lack of commitment and resistance to change
o Fear formal analysis processes will reduce
management’s decision-making power
o Fear previous intuitive decisions exposed as
inadequate
o Uncomfortable with new thinking patterns
o Action-oriented managers may want “quick and
dirty” techniques
o Management support and user involvement are
important
Implementering - Nie Net Die Finale Stap
Implementation – Not Just the Final Step
• Gebrek aan toewyding deur kwantitatiewe analiste
• Lack of commitment by quantitative analysts
o Analiste behoort betrokke te wees by die probleem
en bekommerd te wees oor die oplossing
o Analysts should be involved with the problem and
care about the solution
o Analiste behoort saam met gebruikers te werk en
hulle gevoelens in ag te neem.
o Analysts should work with users and take their
feelings into account
Vir Vrydag
For Friday
• Doen die huiswerk onder assessering
• Do the homework under assessment
o Dit is voorbereiding vir vrydag se klas.
o This is preparation for Friday's class.
o Verstaan die basies theorie en werk deur die handbook
(Dit is belangrik vir die onderrigtoets wat vrydag
plaasfind)
o Understand the basic theory and work through the
handbook (This is important for the teaching test
that takes place on Friday).