Schedule

Question 1

Schedule Network Diagram vs Critical Path Methd vs Critical Path?

Answer 1

• SND: Master schedule depiction of relationships btw activities
• CPM: Sched analysis method calculate shortest path for project, float for each activity, and possible start and finish dates for each activity.
  
  • Used on SND path w/ 0 float is CP
• CP: : Path along activities which any delays would cause project to be delayed. Longest duration path through SND, chain of paths w/ least amount of float.

Question 2

Study Further

Need to know scheduling sequence for Define actv, seq actv, estimate actv durations, dev sched and Resource Mgmt: Plan resc mgmt. and estimate actv dur

Answer 2

1. Plan Project Schedule Process: Process to develop and control project Schedule
2. Define Activities: Decompose Work packages to make activity list
3. Sequence Activities: See what are predecessor/successor orders and creating a schedule network diagram.
   * 4 types of relationsips: FS, SS, SF, FF
   * 4 types of Dependencies: Mand, discrectionary, internal, external
   * Leads and lags

Question 3

Types of activity dependencys?

Answer 3

Mandatory, discretionary, internal, external

Question 4

What is Lead time and Lag time?

Answer 4

Used in Precedence relationships btw activities.

Lead: Start an activity PRIOR to the preceding activity; getting a head start on the activity. Pull activity forward to now.
* Pulling a succor activity forward to present prior to a preceding activity to get head start on it.
* Ex FS relationships btw 2 actv, w/ 2 day LEAD= –2(negative number pulling activity forward to present.
* FS: Act A -> FS-2D -> Act E

Lag: Delay the start of the preceding activity.
* FS relationships btw 2 actv, w/ 3 day LAG= +2(Positive) pushing activity further back
* FS: Act A -> FS +3D -> Act E

** Preceding Activity def: is a task that must be completed before another task can begin. Predecessor.
A(Predecessor)>B(Successor)
* Succeding activity: task that begins after another task has finished.

Question 5

3 point estimate formulas?

Answer 5

Triangular Est: O + ML + P/ 3
Pert(beta Distr): O + 4ML + P / 6

Question 6

Types of float:
1. Free Float
2. Total Float:
3. Project Float:

https://projectmanagementacademy.net/resources/blog/free-float-vs-total-float/

Answer 6

• Free float= activity float, amount of time activity can be delayed w/out delaying the earliest following activity.
• Formula: ES(
• Total Float: Amount activity can be delayed w/out delaying project completion date
  
  • Formula: LF-EF or LS - ES
• Project float: Amount of time project can be delayed without impacting an imposed deadline or comitment by the PM
  
  • Imposed deadline - planned finish date.

Question 7

Mapping Precedence relationships
FS
SF
FF
SS

Answer 7

Tip: reading and applying relationships on predence relationship A>B
*Relationship[a,b], b is 2nd activity sucessor, a is predecessor activity.
* Reading Relationship exs: [a=act1 pred, b=act2 succ]
* FS=[a,b], b has to start before a can finish
* SF=[a,b], b has to finish before a can start
* SS=[a,b], b has to start before a can start
* FF=[a,b], b has to finish before a can finish
* Drawing arrow relationship: Each activity box sides represent Start(left side box), Finish(right side of box)
*

Question 8

Schedule Estimating
Give example of Accuracy and Precision for estimating days

Answer 8

Precisions: How precise the timeframe is:
* Less Precise: Years, months
* More Precise: hours, minutes, seconds

Accuracy: Range of estimation 53 days to 75 days.
* Think Rough order mag(-25 to 75% accuracy low accuracy
* Defnitieve est: -5 to +10% higher accuracy.

Question 9

Which is the CP of all the paths?
ABCF= 34wks
ADEF= 40wks
ABEF=38wks

Answer 9

ADEF= 40wks
CP is the path with longest duration. Also means this is the shortest amount of time we can complete the project.

Question 10

Network Diagram steps

Answer 10

Forward Pass:
Act 1: ES= Start at 0
* Rule start at zero then add duration. sucessor activity keep number don’t add 1+XX.
EF= ES + Dur
Act 2 ES= Act 1(LS)
* Rule: for activities with 2 predecessors pick biggest. Forward = bigger
* Fill all forward top passes.
Critical Path
* Last Activity LS = Paths total dur
* Last Act LF = LS
* Last Act Float = 0 = LS- LF

Backward Pass
* LS = Dur - LF; Work bottoms all way back
* Rule: If two activities Successors to activity pick smalled for bottom backawrd pass

Float = LS-ES or LF-EF