Tag Archives: Estimating

Function Point Analysis (FPA) – Creating Stability in a Sea of Shifting Metrics

Years ago when Karl Weigers (Software Requirements) introduced his  “No More Models” presentation the IT landscape was rife with new concepts ranging from Extreme Programming to the Agile Manifesto to CMMI’s (multiple models), to Project/Program/Portfolio Management.

Since then, the rapidity of change in software and systems development has slowed, leaving the IT landscape checkered with agile, hybrid, spiral and waterfall projects.  Change is the new black, leaving busy professionals and project estimators stressed to find consistent metrics applicable to the diverse project portfolio.  Velocity, burn rates, story points and other modern metrics apply to agile projects, while defect density, use cases, productivity and duration delivery rates are common on waterfall projects.

What can a prudent estimator or process improvement specialist do to level the playing field when faced with disparate data and the challenge to find the productivity or quality “sweet spot”?  You may be surprised to find out that Function Point Analysis (FPA) is part of the answer and that Function Points are as relevant today as when first invented in the late 1970’s.

What are function points (FP) and how can they be used?

Function points are a unit of measure of software functional size – the size of a piece of software based on its “functional user requirements,” in other words a quantification that answers the question “what are the self-contained functions done by the software?”

Function points are analogous to the square feet of a construction floor plan and are independent of how the software must perform (the non-functional “building code” for the software,) and how the software will be built (the technical requirements.)

As such, functional size, (expressed in FP,) is independent of the programming language and methodology approach:  a 1000 FP piece of software will be the same size no matter if it is developed using Java, C++, or other programming language.

Continuing with the construction analogy, the FP size does not change on a project whether it is done using waterfall or agile or hybrid approaches.  Because it is a consistent and objective measure dependent only on the functional requirements, FP can be used to size the software delivered in a release (a consistent delivery  concept) on agile and waterfall projects alike.

WHy are fp a consistent and stable measure?

The standard methodology to count function points is an ISO standard (ISO/IEC 20926) and supported by the International Function Point User Group (IFPUG.)  Established in 1984, IFPUG maintains the method and publishes case studies to demonstrate how to apply the measurement method regardless of variations in how functional requirements are documented.  FP counting rules are both consistent and easy to apply; for the past decade the rules have not changed.

RELEVANCE OF fp in today’s it environment

No matter what method is used to prepare and document a building floor plan, the square foot size is the same.  Similarly, no matter what development methodology or programming language is used, the function point size is the same.  This means that functional size remains a relevant and important measure across an IT landscape of ever-changing technologies, methods, tools, and programming languages.  FP works as a consistent common denominator for calculating productivity and quality ratios (hours / FP and defects / FP respectively), and facilitates the comparisons of projects developed using different methods (agile, waterfall, hybrid, etc.) and technical architectures.

consistency reigns supreme

THE single most important characteristic of any software measure is consistency of measurement!

This applies to EVERY measure in our estimating or benchmarking efforts, whether we’re talking about effort (project hours), size (functional size), quality (defects), duration (calendar time) or customer satisfaction (using the same questionnaire.)  Consistency is seldom a given and can be easily overlooked – especially in one’s haste to collect data.

It takes planning to ensure that every number that goes into a metric or ratio is measured the same way using the same rules.  As such, definitions for defects, effort (especially who is included, when a project starts/stops, and what is collected), and size (FP) must be documented and used.

For more information about Function Point Analysis (FPA) and how it can be applied to different software environments or if you have any questions or comments, please send me an email (dekkers@qualityplustech.com) or post a comment below.

To a productive 2016!


Measurement and IT – Friends or Frenemies ?

I confess, I am a software metrics ‘geek’… but I am not a zealot!  I agree that we desperately need measures to make sense of the what we are doing in software development and to find pockets of excellence (and opportunities for improvement), but it has to be done properly!

Most (process) improvement models, whether they pertain to software and systems or manufacturing or children or people attest to the power of measurement including the CMMI(R) Capability Maturity Model Integration and the SPICE (Software Process Improvement Capability dEtermination) models.

But, we often approach what seems to be a simple concept – “Measure the Work Output and divide it by the Inputs” back asswards (pardon my French!)

Anyone who has been involved with software metrics or function points or CMMI/SPICE gone bad can point to the residual damage of overzealous management (and the supporting consultants) leaving a path of destruction in their wake.  I think that Measurement and IT are sometimes the perfect illustration of the term “Virtual Frenemies” I’ll lay claim to it!) when it comes to poorly designed software metrics programs.  (The concepts can be compatible – but you need proper planning and open-minded participants! Read on…)

Wikipedia (yes, I know it is not the best source!) defines “Frenemy (alternately spelled “frienemy“):

is a portmanteau of “friend” and “enemy” that can refer to either an enemy disguised as a friend or someone who’s both a friend and a rival.[1] The term is used to describe personal, geopolitical, and commercial relationships both among individuals and groups or institutions. The word has appeared in print as early as 1953.

Measurement as a concept can be good. Measure what you want to improve (and measure it objectively, consistently, and then ensure causality can be shown) and improve it.

IT as a concept can be good. Software runs our world and makes life easier. IT’s all good.

The problem comes in when someone (or some team) looks at these two “good” concepts and says, let’s put them together, makes the introduction, and then walks away.  “Be sure to show us good results and where we can do even better!” is the edict.

Left alone to their own devices, measurement can wreak havoc and run roughshod over IT – the wrong things are measured (“just measure it all with source lines of code or FP and see what comes out”), effort is spent measuring those wrong things (“just get the numbers together and we’ll figure out the rest later”), the data doesn’t correlate properly (“now how can we make sense of what we collected”), and misinformation abounds (“just plot what we have, it’s gotta tell us something we can use”).

In the process, the people working diligently (most of the time!) in IT get slammed by data they didn’t participate in collecting, and which often illustrates their “performance” in a detrimental way.  Involvement in the metrics program design, on the part of the teams who will be measured, is often sparse (or an afterthought), yet the teams are expected to embrace measurement and commit to changing whatever practices the resultant metrics analysis says they need to improve.

This happens often when a single measure or metric is used across the board to measure disparate types of work (using function points to measure work that has nothing to do with software development is like using construction square feet to measure landscaping projects!)

Is it any wonder that the software and systems industries are loathe to embrace and take part in the latest “enterprise wide” measurement initiative? Fool me once, shame on you… fool me twice, shame on me.

What is the solution to resolving this “Frenemies” situation between Measurement and IT?  Planning, communication, multiple metrics and a solid approach (don’t bring in the metrics consultants yet!) are the way.

Just because something is not simple to measure does not make it not worth measuring – and measuring properly.

For example, I know of a major initiative where a customer wants to measure the productivity of SAP-related projects to gain an understanding of how the cost per FP tracks on their projects compared to other (dissimilar) software projects and across the industry.

Their suppliers cite that Function Points (a measure of software functionality) does not work well for configurations (this is true), integration work (this is true), and that it can take a lot of effort to collect FP for large SAP implementations (can be true).  However, that does not mean that the productivity cannot be measured at all!  (If all you have is a hammer, everything might look like a nail.)

It will require planning and design effort to arrive at an appropriate measurement approach to equitably and consistently track productivity across these “unique” types of projects. While this is non-trivial, the insight and benefits to the business will far exceed the effort.  Resistance on the part of suppliers to be measured (especially in anticipation of an unfair assessment based on a single metric!) is justified, but a good measurement approach (that will fairly measure the types of effort into different buckets using different measures) is definitely attainable (and desired by the business.)

The results of knowing where and how the money is “invested” in these projects will lead to higher levels of understanding on both sides, and open up discussions about how to better deliver!  The business might even realize where they can improve to make such projects more productive!

Watch my next few posts for further details about how to set up a fair and balanced software measurement program.

What do you think?  Are measurement and IT doomed to be frenemies forever? What is your experience?

Have a good week!

Estimating Before Requirements with Function Points and Other Metrics… Webinar Replay

On June 7, 2012, I conducted an hour-long webinar on “Estimating Before Requirements with Function Points and Other Metrics” before a worldwide audience spanning a myriad of software development specialties/industries and across many countries.

In the event that you missed the live webinar or would like to listen/view the replay, it is available (at no charge) at http://www.qsm.com/Webinars/Estimating-before-Requirements

At the end of the webinar, I offered to send attendees several papers (also downloadable from this link) as well as a Scope Management primer.  If you are interested, please send an email to me at: dekkers (at) qualityplustech (dot) com.

Let me know what you think of the concepts and the webinar!