Showing posts with label Proj Mgmt. Show all posts
Showing posts with label Proj Mgmt. Show all posts
Wednesday, March 19, 2014
Wednesday, January 01, 2014
Project Planning with Sticky Notes
Wednesday, November 20, 2013
Techniques of Demand Forecasting
Broadly speaking, there are two
approaches to demand forecasting- one is to obtain information about the
likely purchase behavior of the buyer through collecting expert’s
opinion or by conducting interviews with consumers, the other is to use
past experience as a guide through a set of statistical techniques. Both
these methods rely on varying degrees of judgment. The first method is
usually found suitable for short-term forecasting, the latter for
long-term forecasting. There are specific techniques which fall under
each of these broad methods.
Simple Survey Method:
For forecasting the demand for existing
product, such survey methods are often employed. In this set of methods,
we may undertake the following exercise.
1) Experts Opinion Poll:
In this method, the experts on the particular product whose demand is
under study are requested to give their ‘opinion’ or ‘feel’ about the
product. These experts, dealing in the same or similar product, are able
to predict the likely sales of a given product in future periods under
different conditions based on their experience. If the number of such
experts is large and their experience-based reactions are different,
then an average-simple or weighted –is found to lead to unique
forecasts. Sometimes this method is also called the ‘hunch method’ but
it replaces analysis by opinions and it can thus turn out to be highly
subjective in nature.
2) Reasoned Opinion-Delphi Technique:
This is a variant of the opinion poll method. Here is an attempt to
arrive at a consensus in an uncertain area by questioning a group of
experts repeatedly until the responses appear to converge along a single
line. The participants are supplied with responses to previous
questions (including seasonings from others in the group by a
coordinator or a leader or operator of some sort). Such feedback may
result in an expert revising his earlier opinion. This may lead to a
narrowing down of the divergent views (of the experts) expressed
earlier. The Delphi Techniques, followed by the Greeks earlier, thus
generates “reasoned opinion” in place of “unstructured opinion”; but
this is still a poor proxy for market behavior of economic variables.
3) Consumers Survey- Complete Enumeration Method:
Under this, the forecaster undertakes a complete survey of all
consumers whose demand he intends to forecast, Once this information is
collected, the sales forecasts are obtained by simply adding the
probable demands of all consumers. The principle merit of this method is
that the forecaster does not introduce any bias or value judgment of
his own. He simply records the data and aggregates. But it is a very
tedious and cumbersome process; it is not feasible where a large number
of consumers are involved. Moreover if the data are wrongly recorded,
this method will be totally useless.
4) Consumer Survey-Sample Survey Method:
Under this method, the forecaster selects a few consuming units out of
the relevant population and then collects data on their probable demands
for the product during the forecast period. The total demand of sample
units is finally blown up to generate the total demand forecast.
Compared to the former survey, this method is less tedious and less
costly, and subject to less data error; but the choice of sample is very
critical. If the sample is properly chosen, then it will yield
dependable results; otherwise there may be sampling error. The sampling
error can decrease with every increase in sample size
5) End-user Method of Consumers Survey:
Under this method, the sales of a product are projected through a
survey of its end-users. A product is used for final consumption or as
an intermediate product in the production of other goods in the domestic
market, or it may be exported as well as imported. The demands for
final consumption and exports net of imports are estimated through some
other forecasting method, and its demand for intermediate use is
estimated through a survey of its user industries.
Complex Statistical Methods:
We shall now move from simple to complex
set of methods of demand forecasting. Such methods are taken usually
from statistics. As such, you may be quite familiar with some the
statistical tools and techniques, as a part of quantitative methods for
business decisions.
(1) Time series analysis or trend method:
Under this method, the time series data on the under forecast are used
to fit a trend line or curve either graphically or through statistical
method of Least Squares. The trend line is worked out by fitting a trend
equation to time series data with the aid of an estimation method. The
trend equation could take either a linear or any kind of non-linear
form. The trend method outlined above often yields a dependable
forecast. The advantage in this method is that it does not require the
formal knowledge of economic theory and the market, it only needs the
time series data. The only limitation in this method is that it assumes
that the past is repeated in future. Also, it is an appropriate method
for long-run forecasts, but inappropriate for short-run forecasts.
Sometimes the time series analysis may not reveal a significant trend of
any kind. In that case, the moving average method or exponentially
weighted moving average method is used to smoothen the series.
(2) Barometric Techniques or Lead-Lag indicators method:
This consists in discovering a set of series of some variables which
exhibit a close association in their movement over a period or time.
For example, it shows the movement of
agricultural income (AY series) and the sale of tractors (ST series).
The movement of AY is similar to that of ST, but the movement in ST
takes place after a year’s time lag compared to the movement in AY. Thus
if one knows the direction of the movement in agriculture income (AY),
one can predict the direction of movement of tractors’ sale (ST) for the
next year. Thus agricultural income (AY) may be used as a barometer (a
leading indicator) to help the short-term forecast for the sale of
tractors.
Generally, this barometric method has
been used in some of the developed countries for predicting business
cycles situation. For this purpose, some countries construct what are
known as ‘diffusion indices’ by combining the movement of a number of
leading series in the economy so that turning points in business
activity could be discovered well in advance. Some of the limitations of
this method may be noted however. The leading indicator method does not
tell you anything about the magnitude of the change that can be
expected in the lagging series, but only the direction of change. Also,
the lead period itself may change overtime. Through our estimation we
may find out the best-fitted lag period on the past data, but the same
may not be true for the future. Finally, it may not be always possible
to find out the leading, lagging or coincident indicators of the
variable for which a demand forecast is being attempted.
3) Correlation and Regression:
These involve the use of econometric methods to determine the nature
and degree of association between/among a set of variables.
Econometrics, you may recall, is the use of economic theory, statistical
analysis and mathematical functions to determine the relationship
between a dependent variable (say, sales) and one or more independent
variables (like price, income, advertisement etc.). The relationship may
be expressed in the form of a demand function, as we have seen earlier.
Such relationships, based on past data can be used for forecasting. The
analysis can be carried with varying degrees of complexity. Here we
shall not get into the methods of finding out ‘correlation coefficient’
or ‘regression equation’; you must have covered those statistical
techniques as a part of quantitative methods. Similarly, we shall not go
into the question of economic theory. We shall concentrate simply on
the use of these econometric techniques in forecasting.
We are on the realm of multiple regression and multiple correlation. The form of the equation may be:
DX = a + b1 A + b2PX + b3Py
You know that the regression coefficients b1, b2, b3 and b4 are the components of relevant elasticity of demand. For example, b1 is
a component of price elasticity of demand. The reflect the direction as
well as proportion of change in demand for x as a result of a change in
any of its explanatory variables. For example, b2< 0 suggest that DX and PX are inversely related; b4 > 0 suggest that x and y are substitutes; b3 > 0 suggest that x is a normal commodity with commodity with positive income-effect.
Given the estimated value of and bi, you may forecast the expected sales (DX), if you know the future values of explanatory variables like own price (PX), related price (Py),
income (B) and advertisement (A). Lastly, you may also recall that the
statistics R2 (Co-efficient of determination) gives the measure of
goodness of fit. The closer it is to unity, the better is the fit, and
that way you get a more reliable forecast.
The principle advantage of this method
is that it is prescriptive as well descriptive. That is, besides
generating demand forecast, it explains why the demand is what it is. In
other words, this technique has got both explanatory and predictive
value. The regression method is neither mechanistic like the trend
method nor subjective like the opinion poll method. In this method of
forecasting, you may use not only time-series data but also cross
section data. The only precaution you need to take is that data analysis
should be based on the logic of economic theory.
(4) Simultaneous Equations Method:
Here is a very sophisticated method of forecasting. It is also known as
the ‘complete system approach’ or ‘econometric model building’. In your
earlier units, we have made reference to such econometric models.
Presently we do not intend to get into the details of this method
because it is a subject by itself. Moreover, this method is normally
used in macro-level forecasting for the economy as a whole; in this
course, our focus is limited to micro elements only. Of course, you, as
corporate managers, should know the basic elements in such an approach.
The method is indeed very complicated.
However, in the days of computer, when package programmes are available,
this method can be used easily to derive meaningful forecasts. The
principle advantage in this method is that the forecaster needs to
estimate the future values of only the exogenous variables unlike the
regression method where he has to predict the future values of all,
endogenous and exogenous variables affecting the variable under
forecast. The values of exogenous variables are easier to predict than
those of the endogenous variables. However, such econometric models have
limitations, similar to that of regression method.
Thursday, August 08, 2013
Three Scope Change Management Techniques
There are
a lot of interesting
scope change management techniques that can be
easily applied to your project. Here are three that will keep you out of
trouble.
Make Sure Only the Sponsor Approves Changes
A typical problem on a project is that the team does not
understand the roles of the sponsor, client and end users in the area of
change management. In general, the project sponsor is the person who is
funding the project. If the client were embodied in one person, it would
be the project sponsor. The people that the project team tends to work with most
often are users. These are the people that use the solution that
the project is building. The end users are the ones that will generally
make requests for changes to deliverables. However, no matter how
important a change is to a user, they cannot approve scope
changes. The sponsor (or their
designee) must give the approval. If the change is important enough the
sponsor will approve it, along with the appropriate budget and
duration changes. If the change is not important enough, it will not be
approved.
Saying 'Yes' to Change Requests
May not Show Good Client Focus
The project manager and project team sometimes think that
they are being client-focused by accepting scope change while still
trying to deliver the project within the original commitments. However,
if the project is delivered late or over budget, it is usually not good
enough to point out all the additional work that was included because of
this 'client focus'.
The sponsor is the primary client representative.
Allowing the sponsor (or their designee) to make scope change decisions
shows good client focus. If the project team or project manager approves
scope changes, he is not showing good client focus from the sponsor's
perspective.
An
Engaged Sponsor Will Often Say 'No' to Scope Change Requests
One of the neat things about enforcing the discipline of
having the sponsor approve scope change requests is that, unless the
change is very important, the sponsor will often say 'no'. The sponsor
is usually someone high in the organization. He normally doesn't want to
hear about requests for small changes. He wants the original project
fulfilled within the original commitments for cost, effort and duration.
Even though it may be hard for the project manager to say 'no', the
project sponsor usually doesn't have any problem saying 'no' to the
people in sponsor's own organization.
Everything You Wanted to Know About Action Items
An
action item is work that requires follow-up execution.
By their nature, action items normally cannot be planned for in advance.
They arise on an ad-hoc basis during meetings or as a by-product of
working on something else. An action item is assigned because there is
not enough knowledge, expertise or time to resolve the item at the time
it originally surfaced.
In many cases, action items are trivial in nature, but in
other cases they can require substantial work to complete. Action items
need to be assigned, worked on later and completed. (If they are not
going to be completed, they should not be called action items. Instead,
simply note that the item will not be followed up on and then forget
about it.) Examples of
action items include forwarding information to someone,
arranging a meeting and providing a quick estimate on a piece of work.
Sometimes an action item is established to investigate an
area where there may be a potential problem. Because of this, action
items are sometimes mixed in with issues. However, this is not right; an
action item should not be confused with an issue. An issue is a problem
which will have a detrimental impact on the project if left unresolved.
An action item may lead to the discovery of an issue or a risk (a
potential issue in the future), but the action item itself is not an
issue.
There are two common approaches used to manage action
items. The best approach is to document the items as activities in the
project schedule. A resource and end-date are assigned as well, and the
activity is then managed and tracked as any normal activity on the
schedule. In general,
this is the better approach to follow, because it keeps the work items
in one place and allows the project manager to enforce the discipline of
knowing ‘if it’s not on the schedule, it will not be worked on.’ This
approach also allows the project manager to see the impact of the action
items on the schedule. For instance, you may have a small action item
that is 3 hours of work. If you assign this action item to a person on
the critical path, you may see the resulting delay to your project.
This may result in you assigning the action item to someone else
instead.
The second approach is to create a section on your
meeting minutes for action items. Action items can be placed here if
they are trivial (less than two hours) and they are scheduled to be
completed by the next meeting. If you use this technique you can start
each meeting with a review of the prior action items to validate that
they are completed and then cross them off the list.
Don't Mix Issues and
Action Items on the Same Log
In many cases, project managers are not using the Issues
Log to identify and track true issues. Many items that are classified as
issues are really risks (potential problems) or just action items.
If you find that your Issues Log has dozens of items on it, you are probably tracking
action items instead. Because issues are large problems, there should not
be many items open at any one time. If you find that your Issues Log is
full of action items, chances are that your true issues are hidden and not worked on as they
should.
Thursday, July 25, 2013
Understand These Three Estimating Concepts
Understand
These Three Estimating Concepts
Estimate in Phases
One of the most difficult aspects of
planning
projects is the estimating process. It can be hard to know exactly what work will be
needed in the distant future. It can be difficult to define and estimate
work that will be done three months from now. It's harder to estimate
six months in the future. Nine months is even harder. There is
more and more estimating uncertainty associated with work that is
farther and farther out in the future.
A good
approach for larger projects is to
break the work into a series of smaller projects, each of which can be
planned, estimated and managed separately with a much higher likelihood
of success. From an estimating perspective, the closest
project can be estimated more precisely, with the subsequent projects
estimated with a higher level of uncertainty. When one project
completes, the next project can be estimated with a higher degree of
confidence, with estimates refined for the remaining projects. This
technique also provides checkpoints at the end of each project so that
the entire initiative can be revalidated based on current estimates to
ensure that it is still viable and worth continuing.
Estimate Fixed Costs and Variable
Costs
You may hear the terms fixed and variable
cost when you are estimating the cost of a project. Variable costs are
those that change relative to how many units are being used. An obvious
variable cost on a project is contract labor. The more hours you use
from a contactor, the more the cost to the project. The
cost of contract labor is variable depending on the number of hours
worked.
Fixed costs are those that are basically
the same for the project regardless of the resources being used. For
instance, if you were building a house, the cost of
the lot would be fixed and would not change based on
the size of the house you built. Similarly, if you outsource part of a project to a
third party for a fixed price, it becomes a fixed cost to the project as
well. Even if the work takes longer or shorter than estimated, your
project cost should still be the agreed upon fixed cost.
Estimate Time-Constrained and
Resource-Constrained Activities
Activities can be classified as time or
resource-constrained based on whether the duration can change if more
resources are applied. An activity is resource-constrained if the
duration changes based on the number of resources applied. For instance,
you might estimate that it will take 80 hours for one person to build a
roof on top of a house. If the person worked forty hours per week, it
would take two weeks to complete the job. If you applied two people to
the job, the effort is still be 200 total effort hours, but the job
would only take one week to complete.
On the other hand, if an activity is
time-constrained, the duration remains the same regardless of the number
of resources applied. For example, lets say one person attends a three-day class. If you send two people to the
class, the class does not get shorter; it still takes three days.
Likewise, the time it takes for concrete to dry, or to mail a letter, is
not impacted by the number of people involved. They just take a certain
amount of time. If you find that applying resources has no impact on the
project duration (or very little impact), then the activity is
time-constrained.
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