January 8, 2012

Description

graph February 17, 2012 DFS Depth First Search Description This function implements algorithm 4.2.1 of Gross and Yellen. The input is a graph and a node to start from. It returns a standard vertex labeling of graph. This is a vector with elements corresponding to the nodes of graph and with values that correspond to point in the depth first search the node is visited. Usage DFS(object, node, checkConn=TRUE) Arguments object An instance of the graph class.

• kegg graph
• original multigraph
• mediated cell adhesion pathway from kegg
• usage data
• nodes
• edge
• vector
• names
• graph
• list

Sujets

• Path
• Multigraph
• Vector

Informations

• Publié par: zieg
• Nombre de lectures: 12
• Langue: English

Extrait

Draft July 1998


BENEFIT-COST ANALYSIS GUIDE





Treasury Board of Canada Secretariat


Ottawa







Table of Contents
Preface iv
For managers .............................................................................................iv
For analysts ................................................................................................iv
Acknowledgements.....................................................................................iv
1. Introduction 5
1.1 Resource-allocation decisions Involve choices................................... 5
1.2 Who is this guide for?......................................................................... 5
1.3 Why benefit-cost analysis?................................................................. 6
1.4 Where benefsis fits into the decision-making process ..... 6
2. The benefit-cost analysis model 8
2.1 Introduction.........................................................................................8
2.2 The benefit-cost analysis framework .................................................. 8
2.3 The steps in benefit-cost analysis....................................................... 8
2.4 Why is a point of view important? 9
2.5 The components of benefit-cost analysis.......................................... 10
2.6 Constructing tables of costs and benefits ......................................... 12
2.7 Accounting conventions....................................................................13
2.8 The report.........................................................................................15
3. Defining fair options 16
3.1 Why are fair options difficult to define?............................................. 16
3.2 An optimised base Case................................................................... 16
3.3 How to construct fair options ............................................................ 17
3.4 Incremental effects analysis ............................................................. 19
4. Measuring and valuing costs and benefits 20
4.1 Introduction.......................................................................................20
4.2 Some Important Concepts................................................................ 20
4.3 Valuing costs and benefits by market prices..................................... 22
4.4 Consumer surplus and producer surplus as components of value.... 23
4.5 its without good market prices .................... 26
4.6 Some examples of difficult-to-estimate values.................................. 27
4.7 Misuse of benefit multipliers ............................................................. 32
5. Time values 34
5.1 Why time matters ............................................................................. 34
5.2 Inflation, nominal dollars and constant dollars .................................. 34
5.3 Changes in relative prices ................................................................ 35
5.4 Future and present values 36
5.5 Discount rates..................................................................................36
5.6 Strategic effects of high and low discount rates................................ 38
i
5.7 The discount rate as a risk variable .................................................. 39
6. Decision rules 40
6.1 Net present value ............................................................................. 40
6.2 Two essential decision rules............................................................. 40
6.3 Unreliable decision rules................................................................... 42
7. Sensitivity analysis 46
7.1 What is sensitivity?........................................................................... 46
7.2 Gross sensitivity...............................................................................46
7.3 What determines sensitivity?............................................................ 47
7.4 Sensitivity and decision making........................................................ 47
7.5 Two-variable sensitivity analysis....................................................... 48
7.6 Graphic analysis of sensitivity........................................................... 49
7.7 Action on sensitivities ....................................................................... 52
8. General approaches to uncertainty and risk 54
8.1 Approaches to quantifying uncertainty-related risk ........................... 54
8.2 Expected values of scenarios 54
8.3 Risk-adjusted discount rates............................................................. 55
8.4 Risk analysis through simulation....................................................... 56
9. Risk analysis 58
9.1 Introduction.......................................................................................58
9.2 The steps of risk analysis ................................................................. 58
9.3 The mechanics of risk analysis......................................................... 59
9.4 Adjusting for the covariance of related risk variables........................ 59
9.5 How many times does the model need to run?................................. 60
9.6 Interpreting the results of the risk analysis........................................ 60
9.7 Decision rules adapted to uncertainty............................................... 61
9.8 Assessing overall risk ....................................................................... 64
9.9 The advantages and limitations of risk analysis................................ 66
10. Probability data 68
10.1 Types of risk variables...................................................................... 68
10.2 Using historical data ......................................................................... 68
10.3 Expert judgement .............................................................................70
10.4 Common probability distributions...................................................... 70
10.5 Risk preferences...............................................................................71
10.6 Common project risks....................................................................... 71
11. Comparing options of different types against different criteria73
11.1 Issues of fairness 73
11.2 Multiple objectives ............................................................................75
12. Key best practices 79
ii
Appendix A: Glossary 80
Appendix B: Questions to ask about a benefit-cost analysis 86
A quick guide ............................................................................................ 86
Appendix C: Selected readings 87
General readings ...................................................................................... 87

Note: The Guide follows the steps of a benefit-cost analysis, from defining the problem and fair comparisons, to
measuring costs and benefits, to dealing with uncertainty and risk. The final chapter discusses what should be done
when the analyst must step outside the benefit-cost framework to consider other criteria.
Each chapter ends with a short summary of best practices and the Guide itself ends with a general summary. There is
a glossary of terms, and terms flagged in bold type in the text can be found in that glossary. Terms in bold italic are
defined where they are introduced. At the end of the Guide there is a bibliography of selected readings, arranged by
topic.

iii
Preface
This Guide provides a framework for benefit-cost analysis. It should be used in submissions to the Treasury Board when
the matter has significant social, economic or environmental implications. A sound benefit-cost analysis should be at the
heart of every business case presented to senior managers and to ministers. The new Guide is part of the Government of
Canada’s focus on evidence-based and analytical decision making.
However, the Guide is not the last word on benefit-cost analysis. It is written to be a useful tool for economists and
non-economists alike. It provides the essential framework and, where possible, indicates best practice; however, it
does not replace the need for training in assessing costs and benefits.
For managers
Managers can use the Guide to help them design and commission benefit-cost analyses and improve their understanding
of the findings. Consistent application of the techniques set out in the Guide is key. Both managers and the Treasury
Board need to be able to compare alternative courses of action in a standard and rigorous way if scarce resources are to
be used to best advantage.
For analysts
This Guide is meant to be an authoritative statement of how a benefit-cost analysis should be undertaken for the
Government of Canada. It replaces the previous Treasury Board Benefit-Cost Analysis Guide which was published in
1976. It provides a consistent framework for comparative analysis but, of course, it does not cover every aspect of the
measurement of benefits and costs. Nor does it replace the professional expertise, which the analyst and the manager
bring to each case. There is no cookbook for good decision making - a good framework is necessary, but insight is
equally necessary.
Acknowled