Exploration Through Example

Example-driven development, Agile testing, context-driven testing, Agile programming, Ruby, and other things of interest to Brian Marick

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Mon, 01 Mar 2004

Ossifying fluidity

IEEE-SA also approved the start of work on IEEE P1648, "Recommended Practice for Establishing and Managing Software Development Efforts Using Agile Methods." This new standard will give those who purchase software a process for establishing, contracting and managing Agile development projects and for working with Agile software developers. It will apply to both technical and project management personnel and will focus on defining and controlling feature development.

For someone like me, who has been - to put it mildly - underwhelmed by the IEEE's desire to standardize software development practices, this announcement is rather alarming. The IEEE's track record has been one of either standardizing prematurely or standardizing things that don't work well. In both cases, IEEE standards have been an impediment to progress. (I am quite fond of 802.11b, though - I'm using it right now.)

If, indeed, this standard is really about how outside contracting organizations might interface with the teams doing agile development, I'm perhaps not so concerned. At least they'll be leaving the teams alone to figure out their own practices. And the fact that standard proposer is the Director of Standards for Computer Sciences Corporation's Defense Group is even cause for optimism: Agile becomes mainstream in a universe that is not notoriously aligned to the values of the Agile Manifesto. But I fear mission creep. And the name is really bad.

[Update: deleted unseemly whining.]

[Further update: later news is grounds for cautious optimism.]

## Posted at 15:47 in category /agile [permalink] [top]

I dub this Yip's Law

Anything can be made measurable in a way that is superior to not measuring it at all. -- Tom Gilb

Corollary: Anything can be made measurable in a way that is inferior to not measuring it at all. -- Jason Yip

## Posted at 13:45 in category /misc [permalink] [top]

Quick tests and slow tests

On the agile-testing mailing list, Jeffrey Fredrick writes:

At my previous company I side-stepped both issues -- defining "unit test" and having them get too slow -- by having two suites of tests, the "quick tests" (QTs) and the "build verification tests" (BVTs). We didn't enforce what sorts of tests people wrote or which suite they added their tests to, but we did requite that the QTs had to all execute in under 5 minutes.

In practice, of course, that meant that most "component isolation tests" ended up as QTs while most "component un-isolation tests" ended up as BVTs.

We've adopted something similar at Agitar where we have a "quick cc build" and a "cc build", where the important measure is the feedback cycle, not a philosophical definition of is _really_ a unit test. http://www.developertesting.com/developer_testing/000023.html

What Jeffrey describes is, I think, an organization of tests according to their virtues as change detectors. When you cannot get all possible change detection feedback fast enough, you arrange things so that you get a lot of the value in a little time.

This is completely orthogonal to other issues like whether the tests are technology-facing or business-facing, written in programmer-ese or customer-ese. How useful are our brains, that they allow us to think about the same thing in more than one way!

## Posted at 10:13 in category /testing [permalink] [top]

Risks of quantitative studies

Jakob Nielsen has an article on risks of quantitative studies. A nice checklist of the way numbers can mislead. My favorite bit:

Even when a correlation represents a true phenomenon, it can be misleading if the real action concerns a third variable that is related to the two you're studying.

For example, studies show that intelligence declines by birth order. In other words, a person who was a first-born child will on average have a higher IQ than someone who was born second. Third-, fourth-, fifth-born children and so on have progressively lower average IQs. This data seems to present a clear warning to prospective parents: Don't have too many kids, or they'll come out increasingly stupid. Not so.

[I'll let you read the article to find out why.]

Note that this ties into my earlier lament on exploratory data analysis. EDA is, in part, a way of persuading numbers to alert you to how you might misinterpret them.

## Posted at 09:29 in category /misc [permalink] [top]