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The Schedule Quality Index™

With the recent launch of the Fuse Schedule Index Calculator, we often get asked, what is the Schedule Quality Index™ and how is it calculated? 

First and foremost the Schedule Quality Index is a means of assessing how well planned a schedule.  It is a single score that is calculated from nine separate schedule check metrics.  The metrics span multiple key attributes, or building blocks of a schedule that together from the underpinnings of a structurally sound schedule. 

The Schedule Quality Index is made up of the following nine checks (metrics):

Missing Logic

In theory, all activities should have at least one predecessor and one successor associated with them. Failure to do so will impact the quality of results derived from a time analysis as well as a risk analysis. This number should not exceed more than 5%.

Logic Density™

This metric calculates the average number of logic links per activity. An average of less than two indicates that there is logic missing within the schedule. An average greater than four indicates overly complex logic, with a high likelihood of redundant links. Therefore, Logic Density™ should be between two and four.

Critical

While a highly critical schedule is not necessarily a sign of poor scheduling, it can indicate a highly risky schedule. Use this metric as a point of reference.

Hard Constraints

Hard, or two-way, constraints such as ‘Must Start On’ or ‘Must Finish On’ should be avoided. Use of such constraints can lead to inaccurate finish dates and a lack of insight into the impact of schedule changes, risk events, and earlier delays.

Negative Float

Negative float is a result of an artificially accelerated or constrained schedule, and is an indication that a schedule is not possible based on the current completion dates.

Insufficient Detail™

Activities with a high duration relative to the life of the project are an indication of poor schedule definition. Detail should be added to the schedule.

Number of Lags

A lag is a duration applied to a logic link often used to represent non-working time between activities such as concrete curing. Lags tend to hide detail within the schedule and cannot be statused like normal activities; therefore, lags should be converted to actual activities with durations.

Number of Leads

A lead, also known as a negative lag, is often used to adjust the successor start or end date relative to the logic link applied. This is a poor practice as it can result in the successor starting before the start of the predecessor.

Merge Hotspot

A merge hotspot is an indication of how complex the start of an activity is. If the number of links is greater than two, there is a high probability that the activity in question will be delayed due to the cumulative effect of all links having to complete on-time in order for the activity to start on time.

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Acumen: It’s all about the schedule

Acumen’s DNA is based on a belief that a sound basis of schedule is the absolute key ingredient to successful project management, a concept otherwise described as :“it’s all about the schedule, stupid”. This concept is not only what we as a company live and breathe every day, but is the drive behind our passion and razor-focus on developing software that helps the project management community improve the practice of CPM scheduling.

 Background

This focus on quality scheduling and project analysis comes from a long history and background in PPM. During the mid 1990’s, I spent several years examining the feasibility of using artificial (AI) systems for generating sound project schedules. This work led to a doctorate as well as an associated commercial software product that is still in use today.  Most importantly, however, I gained a deep understanding of the required mechanics and integrity that is needed to accurately forecast work in the form of a CPM schedule.

A Shift in Focus

During the next twenty years of my career I saw many CPM scheduling tools get faster, more powerful, and more collaborative, while schedule quality remained mediocre at best.  I was continually frustrated that so many projects failed to recognize the importance of this CPM integrity, which in turn bred unrealistic forecasting and unachievable project goals.  

Another unanswered question I kept coming back to was “how can a project forecast a single deterministic completion date given so much uncertainty going forward?” This led to a shift in focus towards the area of project risk analytics. As one of the principles of what was at the time the Pertmaster risk analysis company, I quickly ascertained two points of fact that essentially become the underpinnings of Acumen today:

  1. A risk-adjusted schedule is much more valuable than a deterministic schedulein terms of helping forecast project completion.  This is true for many reasons including:
    • It accounts for uncertainty and complexity of the work being conducted
    • It accounts for overly optimistic planning
    • It encourages the identification of risk events and more importantly the required response to risk (mitigation) by the project team
    • It provides a range of schedule forecasts against which execution can be tracked and controlled
  2. While highly insightful, a risk model is only as sound as the two moving parts within the model itself:
    • The integrity of the underlying deterministic CPM schedule
    • The validity of the risk ranges, inputs and scores provided by the project team

While a risk tool such as Primavera PRA/Pertmaster is extremely fast and powerful in it’s ability to run a schedule-based Monte Carlo simulation, the results are only ever as valid as the inputs that are fed into it. While this is a notable challenge for cost-risk models, forschedule-risk models it is, at best, a mission critical factor and, at worst, it is the ultimate downfall.

And then there was Acumen…

Within this context, Acumen was born from the recognized need to help improve schedule models (irrespective of whether they are deterministic CPM or non-deterministic risk-adjusted schedules).  To help with achieving this, Acumen developed a schedule maturity framework known as “S1 > S5”™. This five-step maturity scale, with steps for taking a project from a non-validated schedule with questionable achievability to one that is sound, risk-adjusted, and has team buy-in, has since helped numerous projects not only improve the integrity of their CPM schedules, but has additionally enabled them to accurately account for the impact of risk and uncertainty, has given them a structured means of compressing or accelerating the schedule, and provided a forum for ensuring the project team is bought into the schedule.

Hand in hand with the S1>S5 methodology, Acumen developed an enterprise project analysis tool, Fuse, to assist in improving schedule maturity through the use of advanced project analytics.

Today, Fuse provides a repeatable means of actually scoring and critiquing the quality of the plan, assessing project performance during execution, and pinpointing as well as understanding the impact of, changes made to the schedule.  Prior to Fuse, this simply wasn’t achievable, with the only options being to use a manual (and therefore timely) analysis or one of a few rudimentary legacy analysis tools.  Because of the combination of over 250 different schedule, cost, risk, EV, performance, and logic checks in the form of advanced analytics and unique-to-Fuse metrics, our customers have often described us as “Mad about Analytics”.   We are continually adding in new metrics and schedule checks based on customer requests and the ever-growing standards from organizations such as AACE, PMI, NDIA, DCMA, and GAO. 

Dr. Dan Patterson, PMP

CEO and President

Acumen

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