To repair complex systems, many resort to "random twiddling and part replacement" (RTAPR) when they're under time and resource constraints. Sadly, RTAPR doesn't work very well. For example, consider a system that has six commercial off-the-shelf components. Let's suppose that it isn't working right. We decide to replace Module 2, which produces no change — the system continues to misbehave. Some might conclude that this proves that Module 2 is OK, but that conclusion might be mistaken. Suppose that the problem lies in the firmware of Module 2, which controls how it operates on the data it receives from Module 1. Since both of our Module 2 boxes contained the same firmware, the system behavior didn't change when we made the swap. A conclusion that Module 2 was not involved in the fault would therefore be incorrect.
A more careful approach can work better than RTAPR. Here are some guidelines that form the basis of what is usually called the scientific method.
- Perform no random experiments
- Random experiments, especially those involving system configuration changes, are unlikely to produce new knowledge. The more complicated the system, the less productive are random experiments.
- Keep excellent records
- Record the Random experiments, especially if
they involve system configuration
changes, are unlikely to
produce new knowledgedetails of all experiments and results. Typically, you won't refer to these notes until you're completely stumped, but that happens with alarming frequency for complex systems. So write the notes so as to make them clear in that kind of desperate situation.
- Try to replicate unwanted behavior
- (a) If the unwanted behavior is reliably repeatable, observe the results of making a minimal change to the system. Any change in behavior can be revealing. (b) If the unwanted behavior isn't repeatable, try to find a system configuration that makes it repeatable, and then go to (a). In all such experiments, controlling the system's containing environment is essential.
- Base all attempts on hypotheses
- Because the input configuration for a complicated system is also complicated, proving that complicated systems work for all required inputs is difficult. Hypotheses about why the system isn't working are equally difficult to prove. Hypotheses can more readily be disproven than proven.
- Therefore, have a testable hypothesis in mind whenever you change the system configuration. Testable hypotheses are of this form (for example): "The fault might be A. If experiment B produces behavior C, then the fault cannot be A." Repeating this process gradually eliminates possibilities until only the truth remains.
- Fail forward
- Devise hypotheses and experiments that cause your investigation to "fail forward." That is, favor experiments that produce useful knowledge whatever the outcome of the experiment. If you make a change and the system starts working, that should help explain what was wrong. And if that same change causes some other result, that, too, should be enlightening information.
Adhering to these guidelines can be difficult, especially under pressure. If deviation is required, make note of it, and note how deviations affect your conclusions. First in this series Top Next Issue
Are your projects always (or almost always) late and over budget? Are your project teams plagued by turnover, burnout, and high defect rates? Turn your culture around. Read 52 Tips for Leaders of Project-Oriented Organizations, filled with tips and techniques for organizational leaders. Order Now!
Your comments are welcomeWould you like to see your comments posted here? rbrenwjRtKwlDmfSswfmMner@ChacePQWsDRQdTDsMdHboCanyon.comSend me your comments by email, or by Web form.
About Point Lookout
Thank you for reading this article. I hope you enjoyed it and found it useful, and that you'll consider recommending it to a friend.
Support Point Lookout by joining the Friends of Point Lookout, as an individual or as an organization.
Do you face a complex interpersonal situation? Send it in, anonymously if you like, and I'll give you my two cents.
More articles on Problem Solving and Creativity:
- Working Lunches
- To save time, or to find a time everyone has free, we sometimes meet during lunch. It seems like a good
idea, but there are some hidden costs.
- Knowing Where You're Going
- Groups that can't even agree on what to do can often find themselves debating about how
to do it. Here are some simple things to remember to help you focus on defining the goal.
- Problem Defining and Problem Solving
- Sometimes problem-solving sessions are difficult because we get started solving a problem before we
know what problem we're solving. Understanding the connection between stakeholders, problem solving,
and problem defining can reduce conflict and produce better solutions.
- How to Reject Expert Opinion: I
- When groups of decision-makers confront complex problems, they sometimes choose not to consult experts
or to reject their advice. How do groups come to make these choices?
- Design Errors and Groupthink
- Design errors cause losses, lost opportunities, accidents, and injuries. Not all design errors are one-offs,
because their causes can be fundamental. Here's a first installment of an exploration of some fundamental
causes of design errors.
Forthcoming issues of Point Lookout
- Coming February 28: Narcissistic Behavior at Work: I
- Briefly, when people exhibit narcissistic behavior they're engaging in activity that systematically places their own interests and welfare ahead of the interests and welfare of anyone or anything else. It's behavior that threatens the welfare of the organization and everyone employed there. Available here and by RSS on February 28.
- And on March 7: Narcissistic Behavior at Work: II
- Narcissistic behavior at work threatens the enterprise. People who behave narcissistically systematically place their own interests and welfare ahead of anyone or anything else. In this Part II of the series we consider the narcissistic preoccupation with superiority fantasies. Available here and by RSS on March 7.
I offer email and telephone coaching at both corporate and individual rates. Contact Rick for details at rbrenCJCARvJOGhniocazner@ChacbJlPyVNXPIcTNRUZoCanyon.com or (617) 491-6289, or toll-free in the continental US at (866) 378-5470.
Get the ebook!
Past issues of Point Lookout are available in six ebooks:
- Get 2001-2 in Geese Don't Land on Twigs (PDF, USD 11.95)
- Get 2003-4 in Why Dogs Wag (PDF, USD 11.95)
- Get 2005-6 in Loopy Things We Do (PDF, USD 11.95)
- Get 2007-8 in Things We Believe That Maybe Aren't So True (PDF, USD 11.95)
- Get 2009-10 in The Questions Not Asked (PDF, USD 11.95)
- Get all of the first twelve years (2001-2012) in The Collected Issues of Point Lookout (PDF, USD 28.99)
Are you a writer, editor or publisher on deadline? Are you looking for an article that will get people talking and get compliments flying your way? You can have 500 words in your inbox in one hour. License any article from this Web site. More info
- The Power Affect: How We Express Our Personal Power
- Many people who possess real organizational power have a characteristic demeanor. It's the way they project their presence. I call this the power affect. Some people — call them power pretenders — adopt the power affect well before they attain significant organizational power. Unfortunately for their colleagues, and for their organizations, power pretenders can attain organizational power out of proportion to their merit or abilities. Understanding the power affect is therefore important for anyone who aims to attain power, or anyone who works with power pretenders. Read more about this program.