4E1 Project Management

4E1 Project Management Planning 2 Estimating and Scheduling

Key Concepts • Estimating • Scheduling • Gantt charts • Network notations

# Best guess Upper estimate Lower estimate 1 2 3 .. 10 Exercise • Take a blank sheet of paper • Divide it into five columns as follows: There should be ten rows to write on.

Test Your General Knowledge • For each item, write (a) best guess and (b) upper and lower estimates that you are 90% confident of. • Distance in miles from Moscow to Santiago (in Chile) • Gold medals won by Finland in summer Olympics 1896-1992 • Area of Greenland in square miles • Year the ballpoint pen was invented • Year the HJ Heinz company was founded • Population of Belize in 1990 • Denmark’s GNP in $US in 1989 • Year that Louis Braille was born • Average depth of Pacific ocean to nearest 1,000 feet • Length in miles of the river Danube

Answers • Distance from Moscow to Santiago is 10,118 miles • Finland won 97 gold medals in summer Olympics 1896-1992 • The area of Greenland is 839,781 square miles • The ballpoint pen was invented in 1938 • The HJ Heinz company was founded in 1876 • The population of Belize in 1990 was 187,000 • Denmark’s GNP in $US in 1989 was $105,238 million • Louis Braille was born in 1809 • The Pacific ocean is 14,000 feet deep on average • The river Danube is 1,770 miles long

Why are Estimates So Often Wrong? • Internal causes • Psychology: over-confidence, optimism, ego • Misjudgement: inexperience, uniqueness of project • Failure to learn from previous projects • External pressures • Management pressure, sales imperative • Other causes • Games, inadequate specifications, unclear objectives • Rarely, bad luck

Example: Software Estimating • How many steps in this C program to convert Fahrenheit to Celsius? #define LOWER 0 #define UPPER 300 #define STEP 20 main() {int fahr for (fahr=LOWER fahr<=UPPER fahr=fahr+STEP) print(“%4d %6.1f\n”,fahr, (5.0/9.0*(fahr-32))}

Experts’ Estimates

Estimating – Broad Strategies • Bases • Experience, similar work in previous projects • Detailed breakdown/WBS • Heuristics e.g. function points • Types • Ballpark, comparative, feasibility, detailed • Top-down vs bottom-up • Risks • Theoretical versus actual resource costs • Cumulative effect of small errors

Acts of God External Factors Fiscal Policy Corporate Strategy Market Conditions Statutory Regulations Working factors Supporting Services Technical capability Communications Planning and Scheduling Attitudes and culture Procedures and systems Resources and capacity Management skills Organisation structure Contribution to results Time Profit Quality Scheduling: Context

The Bar (Gantt) Chart Henry Gantt Task Implicit dependency Design Purchase materials Overlap Set up Lag Manufacture Explicit dependency Test Time

Gantt Charts in Practice

Exercise • Draw a Gantt chart for your “Gulliver Experience” project, showing only the top-level tasks (i.e. about 7 phases) • Planning • Project plan, agree requirements • Outsource project • Issue request for tenders, review proposals, award contract • Design • Architectural design, detailed design and blueprints, order materials • Move TCD administration • Prepare new location, move • Construction • Site preparation, building, fit-out • Set up business • Establish company, hire staff, implement systems, marketing • Commence business operations • Add estimated durations, start and end dates, dependencies and resources

5 2 9 1 7 3 6 8 4 Get up Eat breakfast Go to college 1 2 3 4 10 20 30 Network Diagrams • Activity on arrow

Activity Properties • Description • Resources: human, other • Work/non-work • Duration • Dates: earliest start, latest finish • Dependencies: predecessors, successors • Other constraints

5 3 5 2 9 1 8 4 1 1 7 4 3 2 4 5 3 6 5 8 4 6 Precedence • Dummy task (dashed line) indicates order • Node 4 precedes node 5 • Therefore tasks 5 and 8 cannot start until task 3 is complete

Types of Network Diagram Two basic types: • Activity on arrow (most intuitive) • Arrow diagrams (ADM) • Critical Path Method (CPM) • Critical Path Analysis (CPA) • Project Evaluation and Review Technique (PERT) • Activity on node (suits computers) • Precedence diagrams (PDM) • Rare but still used • Method of potentials (MPM) • Activities on circular nodes

Go to college 30 Get up 10 Eat breakfast 20 Precedence Diagrams

Precedence Diagrams - Dummy Tasks • Not customary but can be useful

Activity AF Activity FV V A F Activity BE Activity FW W B Activity CE Activity FX X E C Activity GY Activity DE Y G D Activity GZ Z Exercise • Redraw this arrow diagram as a PDM (a) with dummy tasks and (b) without dummy tasks

AF FV BE FW CE FX DE GY GZ Solution (without dummy tasks)

Dummy 1 AF FV BE FW Dummy 2 CE FX DE GY GZ Solution (with dummy tasks)

Activity Code Activity Description Duration Elapsed time Earliest Start Date Latest Start Date Earliest Completion Date Latest Completion Date Resources Assigned Network Notations - Example 1 Networks use standard notation as follows: Screed Floor B1.3 D =26 Bus = 35 ES = 2/10 LS = 15/10 EC = 6/11 LC = 23/11 Res = FEB, JH

Earliest finish time Latest event time Earliest start time Duration Activity identifier 5 10 15 25 Activity identifier and description Resources required. 10 17 8 3 18 Earliest event time Latest start time Total float Latest finish time Network Notations - Example 2

Network Notations - Example 3 Duration Earliest Start Time Earliest Finish Time Task Description 14/11/06 5 15/12/06 4.2.3 Specify Hardware 3/12/06 17 18/1/05 JO’D €2,500 0% Task ID Latest Finish Time Latest Start Time Budget Resources/ Responsibility %Complete Total Float

Gantt vs Network • Both used widely • Gantt • Simpler, easier to grasp • Limited in ability to show dependencies • Easily cluttered • Networks • More meaningful, more information • Harder to read • Often large and complex

Summary: Key Points • Estimating • Part science, part art • Tools help but judgment is required • Gantt charts • Most basic tool; intuitive but limited • Network (arrow/precedence) diagrams • More powerful, less intuitive

4E1 Project Management