PMPTerminologies

PMP Terminologies
In continuation of the terminology discussion we are going
to capture about Time Management knowledge area. Here are a few.
Duration vs Effort
When we are
estimating the time required to complete an activity, we use the words effort,
duration etc… Is duration and effort same? NO.
Effort is the actual amount of time spent
to carry out an activity. This can be expressed in terms of person hours, man
days or man months. It shows the total number of hours/days/months that each
person spent working on each of the activities.
Duration is the amount of time taken to carry
out an activity. That is the start time and end time which is nothing but the
time elapsed to complete the activity. Duration is measured in hours/days etc..
This doesn’t count the number of people working on the activity.
For example:
An activity takes 4 hours to work by one person. The person who is carrying out this activity
contributes one hour per day. So the total days taken will be 4 days. Here the
effort is 4 hours where as the duration is 4 days.


Resource


Effort(Hours)


Duration(Everyday effort)


Total duration(Days)




Day1


Day2


Day3


Day4




a


4


1


1


1


1


4




b


2





1


1





2




c


3


1





1


1


3



Crashing vs Fast tracking
After the
arrival of total duration of the project by estimation technique, the project
manager presents the schedule to the PMO/Sponsor/Customer. But the Customer says that the duration has
to be reduced without comprising on the scope of the work. Now what is the left
out option for Project Manager, either he/she has to add resources or has to
run the activities in parallel.
Crashing is nothing but adding resources. Of
course when the crashing happens, the cost increases, because you are adding
extra resources.


















Fast tracking represents the activities to be
carried out in parallel instead of series. Here the disadvantage is that, it
increases the risk in the area of may be quality as the activities are
performed parallel.


Forward Pass vs Backward Pass
After the
arrival of critical path in the given network diagram, we need to track closely
the activities which are coming under the critical path. And for the activities
which are not in the critical path the tracking can be the normal way. But when
we say normal, need to know what is the degree of level. This can be determined
by the parameter called float or slack. To find the float or the slack
we have to perform the Forward pass and Backward pass.
Forward pass is moving through the network
diagram from start to finish and covering all the paths.
Backward
pass is moving through the network diagram in the reverse way or from Finish to
start of the network diagram and covering all the paths.
When we do
the forward and backward pass, will end up with values of Late Start (LS), Late
Finish (LF), Early Start (ES) and Early Finish (EF).
Float is the
difference of LS and ES or LF and EF, i.e. LS-ES
or LF-EF.
Free float vs Total float
Free float is an
amount of time that a schedule activity can be delayed without delaying the
early start of any immediately following schedule activities.
Total float is
the total amount of time that a schedule activity may be delayed from its early
start date without delaying the project finish date, or intermediary milestone.
In the given example below the total float for activity 3 is
5 and the free float is also 5(ES of activity 5-EF of activity 3). Similarly
the free float for activity 2 is 0.


Lead vs Lag
Lead is advancing an activity in terms of
schedule to overcome the risk if anything that may happens to the project.
For example:
You need an equipment 20 days from now and you are importing from outside.
Assume that it takes 15 days from the day of order. Instead of waiting for 5
more days from now, order now itself so that you can avoid the possible delay.
That is advancing the order day by 5 days.
Lag is deliberately delaying the successor activity.
For Example:
There are two activities. The first one is painting and second one is framing.
After painting will give some time so that the paint will dry and then only
will start framing. Deliberate delay in the successor activity is called Lag.