CPM Calculations Part 1 – The Basics

This is the first of a series of three videos explaining how the CPM algorithm works. It helps you fully understand where your schedule dates come from. This video gives you a complete understanding of why CPM remains the most popular and effective tool to bring your project in on time.


CPM Calculations Part 2 – Lags, Constraints & Project Finish

This is Part 2 of the CPM Calculation presentation. It goes beyond the basic forward/backward pass calculations and discussion of total and free float and introduces additional aspects of scheduling, including lags, constraints and specified project finish dates.

CPM Calculations Part 3 – The Critical Path Explained

This video explains the real meaning of critical path and illustrates why PMI’s simplistic definition of critical path is not accurate, or at least not complete. It concludes with a suggestion to set things right.

Earned Value, Clear and Simple

Below is an article on this popular topic. It first appeared in 1999 and has retained its popularity over the years. You can read it here or click the Download button.

EAC Error in MS Project

MS Project does not calculate the EAC correctly all the time at higher levels of the WBS.  This video explains why and offers a work-around so that you can report to your stakeholders with confidence.

Scaling the PMBOK® Guide:  The 20-minute Project

New students constantly ask:  “But I’m not building a power plant or flying to the moon.  What will this course do for ME?”  And, of course, the big worry is that the PMBOK® Guide is way too complex for most projects.  So, I illustrate that the material in the PMBOK® Guide is totally applicable to any project, even to the smallest project I can think of, buying groceries.

In the following scenario, all caps words represent either a Knowledge Area or an artifact from the PMBOK® Guide.  This will help show the connection between this simple project and the “complexity” of the Guide.

First off, do we have a PROJECT?  It certainly is; we have a temporary endeavor, assuming the husband does return home with the groceries, and there is an objective, bringing groceries home; and there is added value as a result of conducting this project.

Was there a BUSINESS CASE for this project?  There certainly was; the value expected to be delivered was a refrigerator and pantry full of food.

Was there a  PROJECT CHARTER?  There certainly was; the PROJECT SPONSOR (i.e. the wife, lol) authorized her husband to engage in this project, giving him authority to expend COMPANY RESOURCES and do what is necessary to deliver a successful result.

So, we have the genesis of our project.  We have a PROJECT MANAGER, a PROJECT TEAM, which happens to be the same as the project manager, and we have various STAKEHOLDERS.  Let us consider the project management functions, aka the Knowledge Areas.

Do we have a defined SCOPE?  We certainly have; using the shopping list as a SCOPE STATEMENT or REQUIREMENTS DOCUMENT, it is clear what the PROJECT OBJECTIVE is.

Is there a project SCHEDULE?  There certainly is; the husband is to be back home within 20 minutes.

Is there a BUDGET?  There certainly is; following an ESTIMATE, a budget of $20.00 was established, including a CONTINGENCY of $3.00 for additional items and price uncertainty.

Is there a MANAGEMENT RESERVE?  There certainly is; since the husband was going to use a credit card, his wife would be consulted via phone in case the store had, unknown to them, raised prices well beyond the couple’s expectations and perhaps received authority to use more money than was in the PROJECT BUDGET.

Are there RESOURCE REQUIREMENTS and availability?  There certainly are; the husband was considered to be available, pre-empting any other activities he might have been planning on.  This was a STRATEGIC MANAGEMENT DECISION.

Is there a PROCUREMENT MANAGEMENT process in play?  There certainly is; following a MAKE-BUY ANALISYS, the couple decided to outsource the bread, milk, bananas, eggs and orange juice in lieu of producing these items themselves.  Is there a PURCHASE ORDER?  There certainly is; by implication of the filled shopping cart, the store agrees to supply the items and the husband agrees to pay.

Is there and INVOICE?  There certainly is; the cashier showed the husband the itemized list and prices with a total amount and the husband used his ACCOUNTS PAYABLE process (his wallet) to make payment.

Are there STAKEHOLDERS involved? There certainly are; besides the couple, there are the store’s staff, other drivers on the streets, as a minimum.

Are there COMMUNICATION issues to be dealt with?  There certainly are; does the husband truly understand the project objectives or is his mind still on the football game he had been watching?  Is the shopping list legible or full of abbreviations?

Are there quality concerns?  There certainly are; the milk is to be as fresh as possible and the date is the QUANTITATIVE METRIC used for that.  The bananas should not be too ripe and the color of the skin is the QUALITATIVE METRIC used for that.  The eggs are to be checked for any broken ones, which are considered to be a defect and the source point inspection in the store (think FACTORY TEST) is the QUALITY TOOL to be used for that.

Is there a QUALITY TEST designed to be performed prior to acceptance?  There certainly is; the wife admonished her husband to be sure to jiggle each egg in the carton because broken ones would be sticking to the carton.

Are there any RISKS to be concerned about?  There certainly arer; another driver might be running a red light on the husband’s way to the store.  The store might be out of acceptable bananas.  The prices might be much higher than anticipated.  The normal road might be blocked due to police activity, requiring the husband to make a detour that would take an extra ten minutes.

Is there a possibility of SCOPE CREEP?  There certainly is; the husband might decide to add beer to the shopping list without consulting the appropriate STAKEHOLDER.

Is there a possibility of a SCOPE CHANGE?  There certainly is; while at the store, the husband receives a call from his wife to add an item to the shopping list, resulting in an authorized SCOPE CHANGE, including an increase in the budget.  The above mentioned CONTINGENCY would cover that.

Is there an AGILE delivery process involved?  There certainly might be; the couple might decide that the ultimate REQUIREMENTS, i.e. the shopping list, would be established sometime while the husband was at the store.  SPRINTS would be in two minute TIME BOXES, and the REQUIREMENTS to be “developed” would be the specific items to be placed into the shopping cart.  Each SPRINT would start with a SPRINT PLANNING MEETING to determine which REQUIREMENT (item on the shopping list) is to be found next; and followed by a SPRINT REVIEW MEETING to determine which items made it into the shopping cart.

Is there review of the project to determine its success?  There certainly is; the wife reviews the items, frowns at the beer, but gives her husband solid hug and a kiss and says:  “Thank you dear.  I left the football game on for you.”

My goodness, did you ever think going shopping would be this complicated?  Do you now realize that all the stuff in the PMBOK® Guide is scalable?  And on top of that, you can tailor the project management practices to the needs of your project.   No need for a voluminous scope statement, no need for a CPM schedule, no need for a lot of detailed management plans; I think you get the idea.  So, no matter how large and complex or how brief and simple your project might be, the materials in the PMBOK® Guide apply.  And needless to say, you would simplify and tailor the processes to suit.

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