Ian Heaps on Fishing

is an excellent (out of print) book by Ian Heaps (isbn 0-907675-02-6). As usual I'm going to quote from a few pages:

The best way to improve is to practice.

You must feed according to how many fish there are and how they are feeding.

There was a method though, and that was slowing the bait down… the caster needing fishing in a very different way to the maggot.

You must keep it as simple as possible: fish as efficiently as you can.

You must learn to feed on a regular basis so that the fish are charged up, and they get to know exactly when the next amount of food, is going to arrive.

Especially on a river which is flowing, the most important thing is to get a feeding pattern going. Then, there are a thousand and one shooting patterns which will catch them.

If you see the float lifting up a bit when it should be bullying its way through the swim, it is not big enough to do the job.

For me, far too many people are obsessed nowadays with fishing light. All too often they do not experiment and put on enough lead.

Generally speaking, I have found that the more lead you can get on the line and still present the bait properly the more, and the bigger, fish you will catch.

Practice makes perfect, and there is no substitute for experimenting yourself.

If you put on a number of smaller shot and bunch them together, you can soon space them out if the feeding pattern changes.

John [Dean] did the same thing as everyone else - only he did everything just a little bit better.

The lady tasting tea

is an excellent book by David Salsburg (isbn 0-8050-7143-2). As usual I'm going to quote from a few pages:

It was a summer afternoon in Cambridge, England, in the late 1920s. A group of university dons, their wives, and some guests were sitting around an outdoor table for afternoon tea. One of the women was insisting that tea tasted different depending upon whether the tea was poured into the milk or whether the milk was poured into the tea.

What I discovered working at Pfizer was that very little scientific research can be done alone. It usually requires a combination of minds. This is because it is so easy to make mistakes.

Galton discovered a phenomenon he called "regression to the mean."

The numbers that identify the distribution are not the same type of "numbers" as the measurements. These numbers can never be observed but can be inferred from the way in which the measurements scatter. These numbers were later to be called parameters - from the Greek for "almost measurements."

Bliss invented a procedure he called "probate analysis." … The most important parameter his model generated is called the "50 percent lethal dose," usually referred to as the "LD-50." … The further you get from the 50 percent point, the more massive the experiment that is needed to get a good estimate.

If you are willing to settle for knowing the two parameters of a normal distribution within two significant figures, you need collect only about 50 measurements.

It is better to do mathematics on a chalkboard than on a piece of paper because chalk is easier to erase, and mathematical research is always filled with mistakes. Very few mathematicians work alone. If you are a mathematician, you need to talk about what you are doing. You need to expose your new ideas to the criticism of others.

In the deterministic approach, there is a fixed number, the gravitational constant, that describes how things fall to the Earth. In the statistical approach, our measurements of the gravitational constant will always differ from one another, and the scatter of their distribution is what we wish to establish in order to "understand" falling bodies.

No test can be powerful against all possible alternatives.

In the near disaster of American nuclear power plant at Three Mile Island power plant in Pennsylvania in the 1980s, the operators of the reactor had a large board of dials and indicators to follow the progress of the reactor. Among these were warning lights, some of which had been faulty and presented false alarms in the past. The prior beliefs of the operators were such that any new pattern of warning lights would be viewed as a false alarm. Even as the pattern of warning lights and associated dials produced a consistent picture of low water in the reactor, they continued to dismiss the evidence.

Kolmogorov called a sequence of numbers collected over time with successive values related to previous ones a "stochastic process."

Attitude, passion

Attitude is a shop somewhere in an airport terminal in USA. I forget where exactly. Possibly Chicago. Passion is a restaurant in Ghent in Belgium.

The Princess Bride

is an excellent book by William Goldman (isbn 0-7475-4518-9). As usual I'm going to quote from a few pages:

It's still my favourite book in all the world. And more than ever, I wish I had written it.

This is my favourite book in all the world, though I have never read it.

Miracles. Giants. True love.

Eyes like the sea before a storm.

We are but poor circus performers.

Absolutely, totally, and, in all other ways, inconceivable

Then one morning, Inigo was gone. In his place were three words: "I must learn" on a note pinned to his pillow.

I am not left-handed.

What you do not smell is called iocane powder.

Don't you rush me, sonny, you rush a miracle man, you get rotten miracles.

I AM THE DREAD PIRATE ROBERTS AND THERE WILL BE NO SURVIVORS.

Authentic happiness

is an excellent book by Martin Seligman (isbn 1-85788-329-2). As usual I'm going to quote from a few pages:

Daddy, do you remember before my fifth birthday? From when I was three until when I was five, I was a whiner. I whined every day. On my fifth birthday, I decided I wasn't going to whine any more. That was the hardest thing I've ever done. And if I can stop whining, you can stop being such a grouch.

All emotions about the past are completely driven by thinking and interpretation.

There are, however, no known ways to enhance forgetting and suppressing of memory directly. Indeed explicit attempts to suppress thoughts will backfire and increase the likelihood of imagining the forbidden object.

If you think about bad things in terms of "always" and "never" and abiding traits, you have a permanent, pessimistic style.

Learned optimism… is about accuracy.

Almost nothing that happens to you has just one cause.

Mindful attention to the present occurs much more readily in a slow state of mind.

Total immersion, in fact, blocks consciousness, and emotions are completely absent.

The mood state Americans are in, on average, when watching television is mildly depressed.

The overarching principle of good listening is validation.

By encouraging cheap success, it produced a generation of very expensive failures.

Every drug that breaks up depression also blocks dreaming.

Agile A-Z Keynote

I attended the excellent Agile .NET 2011 conference in Ghent, Belgium this week. Jason Gorman pulled out at the last minute and Erik asked me if I'd step in and do the keynote. I said yes of course and prepared this on the train+plane there.

An Agile A to Z

View more presentations from JonJagger.

Waiting work wall

One of the things I do a lot when visiting software groups is simply sit with individuals as they work. Sometimes the person I'm sitting next to is a really superb developer. They finish their work fast and to a high standard and hand the work on to the next person downstream. This next person may also be really skilled but their work might just inherently take longer. If the amount of work passed on exceeds the capacity of the next person then a growing batch of work-waiting-to-be-started-by-the-next-person will naturally form and grow.

This batch of work-waiting-to-be-started-by-the-next-person is waste. That's well known and well written about. What's not so obvious and not so well written about is how it encourages silos to form. It literally forms a barrier between the increasingly separated silos that form on either side of it.

Think of each waiting-work-item as a brick in a wall. But not a long, low, queue-shaped wall that's easy to see over. Rather, a short, high wall. One that you can't see over. One that hinders communication.

The amount of waiting-work between two silos is inversely proportional to the lack of communication between the two silos. The more waiting-work, the less the communication. The less communication the more waiting-work. Round and round it goes.

So, if you have some really superb developers then beware. They might be creating a downstream wall of waiting-work around which silos are forming.

Zen in the martial arts

is an excellent book by Joe Hyams (isbn 0-87477-101-3). As usual I'm going to quote from a few pages:

At least empty your cup and try.

Those who are patient in the trivial things in life and control themselves will one day have the same mastery in great and important things.

The martial artist develops through practice until it becomes mechanical and then spontaneous.

When you lose your temper, you lose yourself - on the mat as well as in life.

The proper system is to think twice more. Patience is part of it. To avoid being intimidated - think more and react less.

Try softer. When one eye is fixed upon your destination, there is only one eye left with which to find the way.

To know and to act are one and the same.

Relaxation and concentration go hand in hand. But too much concentration defeats itself.

Most of the time we generate our own fears, and this is especially true when we confront an unfamiliar situation that shatters confidence.

Years ago I thought too much about what I had to do, laboured over it, put off difficult chores, waited for the mood to be right or the creative juices to flow. Now I just do it without conscious effort. It flows because the work and I are one, and not in conflict with each other.

The only reason men fight is because they are insecure; one man needs to prove that he is better or stronger than another. The man who is secure within himself has no need to prove anything with force, so he can walk away from a fight with dignity and pride.

C will live forever

My good friend Olve Maudal said something the other day that caught my ear. He said C will never be replaced. I think he's right. Languages like Java and Ruby are great languages when you don't need to get near to the metal. But if you do need to get near to the metal, then C has already filled that niche so well that it's hard to see it ever being replaced. You might say that a language like C, but without C's penchant for undefined behaviour, could somehow replace C. I don't think so. The point is that the sweet spot for a language designed to be used close to the metal is a language that deliberately does not get rid of its undefined behaviour. Because that is part of it being in the sweet spot. And besides, C has been around long enough that if a language was going to replace C wouldn't it already have happened?

Situated learning - Legitimate peripheral participation

is an excellent book by Jean Lave and Etienne Wenger (isbn 0-521-42374-0). As usual I'm going to quote from a few pages:

The world carries its own structure so that specificity always implies generality (and in this sense generality is not to be assimilated to abstractness).

Reversing production steps has the effect of focusing the apprentice's attention first on the broad outlines…

The fact that the work was done in an interaction between members opened it up to other members of the team.

There is anecdotal evidence that where the circulation of knowledge among peers and near-peers is possible, it spreads exceedingly rapidly and effectively.

A learning curriculum is thus characteristic of a community.

Understanding and experience are in constant interaction.

Mirroring the intricate relationship between using and understanding artefacts there is an interesting duality inherent in the concept of transparency. It combines the two characteristics of invisibility and visibility… It might be useful to give a sense of this interplay by analogy to a window. A window's invisibility is what makes it a window, that is, an object through which the outside world becomes visible. The very fact, however, that so many things can be seen through it makes the window itself highly visible, that is, very salient in a room, when compared to, say, a solid wall. Invisibility of mediating technologies is necessary for allowing focus on, and thus supporting visibility of, the subject matter.

World class match fishing

is an excellent book by Kevin Ashurst (isbn 0-304-29729-1). As usual I'm going to quote from a few pages:

I always try to visualise what is happening under the water, and the only concrete clues I can count on are the bites, or the lack of them.

When loose-feeding for roach and dace, it always pays to shuffle the tackle when bites cease. Moving a shot an inch or two, or altering the depth slightly, works so frequently that one has to assume that the fish, as well as becoming wary because of their diminishing numbers, also get shy of baits coming to them in precisely the same way all the time.

Good loose-feeing is one of the key factors affecting success in match angling, and the difficulty of getting it right is one of the reasons why I set so much store by practising for big matches.

The starting point is the knowledge that you cannot scare fish away if they are not there to begin with.

I always think fish behave a bit like birds. If you scatter breadcrumbs on a lawn the birds begin eating it from the edges, rarely alighting in the middle, and I reckon fish behave the same way.

The trick to drop fishing is to read the signs, and the most important one is getting a caster shelled or a maggot sucked without seeing a bite.

A stick float is quite heavy in relation to its size, and at any sort of range we can cop for a splashy sort of strike.

The fish in shallow water tend to be shy. They usually come into the baited area, pick up a bait and bolt.

The original choice of float is obviously dictated by the distance to be cast and the conditions on the day, and the aim should be to achieve whatever distance is required easily. It is better to overcast and pull back than to fall short and have to cast again.

It goes without saying that the kinds of bites we can expect depends entirely on the way the fish are behaving on the day, and how we are shotted in response to that behaviour.

To be perfectly honest the appearance of my floats has never interested me. I never even thought about them in the artistic sense until Colin brought it up, but I suppose the answer lies under the general heading of ignoring everything which is not essential. I devote a lot of time, thought and energy to my fishing, but only to those departments which require time, thought and energy.

More CyberDojos

I ran a CyberDojo at the excellent Tampere goes Agile conference recently (left photo). It got a 100% green card vote.

A few days later I ran another CyberDojo for the devs at Solita Oy, also in Tampere. A nicer bunch of people you couldn't ask to meet.

And a few days after that I ran yet another CyberDojo at the Ericsson Agile conference in Helsinki (right photo). @jussikm @htaubert and @karmolis tweeted that it was the most fun they'd had at work in 2011.

ALE CyberDojo Ice Breaker

I ran a mass-participation CyberDojo "keynote" at the excellent ALE conference in Berlin recently. 10 laptops were setup with a Yahtzee refactoring exercise in Java. Over 200 people participated. The aim was not to write code - it was to mix people up and get lots of energy into the conference right at the start. I think it worked very well.

We are what we say

Steven Fry wrote a piece for Radio Times about his new BBC2 series Fry's Planet Word. The following snippets caught my attention.

Most social groupings of young people have their own private language, catchphrases and nicknames for people and processes.

All that bright individual verbal clothing is put away for the workplace and dull, pretentious verbal suits are worn in their place. Never was the word "suit" less... well... suitable. The memos, meetings and conferences of the workplace are couched in agglomorations of phrases as soulless, bloodless, styleless and depressing as they grey carpets, strip lighting and hessian partitions that constitute their physical environment. Sick-building syndrome is now well understood, sick language syndrome perhaps less so.

We may be what we eat, but we most certainly are what we say.

They reminded me again of the importance of precision listening.

Brain rules

is an excellent book by John Medina (isbn 978-0-9797777-4-5). As usual I'm going to quote from a few pages:

Students learn better from words and pictures than from words alone.
Students learn better when corresponding words and pictures are presented simultaneously rather than successively.
Students learn better when corresponding words and pictures are presented near to each other rather than far apart on the page or screen.
Students learn better when extraneous material is excluded rather than included.
Students learn better from animation and narration than from animation and on-screen text.

When the brain is fully working, it uses more energy per unit of tissue than a fully exercising quadricep.

Charles Darwin noted… the brains in wild animals were 15 to 30 percent larger than those of their tame, domestic counterparts.

Studies show that a person who is interrupted takes 50 percent longer to accomplish a task. Not only that, he or she makes up to 50 percent more errors.

Spaced learning is greatly superior to massed learning.

A great deal of research shows that thinking or talking about an event immediately after it has occurred enhances memory for that event.

Students are expected to known certain things by certain grades. Curiously absent from this model is how durable that learning remains after the student completes the grade.

When people become sleep-deprived, their ability to utilise the food they are consuming falls by about one-third.

Sleep loss cripples thinking in just about every way you can measure thinking.

Vision is by far our most dominant sense, taking up half of our brain's resources.

All I need to know about manufacturing I learned in Joe's garage

is an excellent book by William B. Miller and Vicki L. Schenk (isbn 0-9630439-3-5). As usual I'm going to quote from a few pages:

I mumbled back something equally unintelligible, the traditional response to somebody whom you aren't sure you've met and whose name you aren't certain of.

"Why is there such a conflict?" he asked. "Both departments are striving for the same thing, the good of the company. Why should they not work together?"

With all that volume flowing through his "factory," even the slightest unplanned act will ripple through everything else with a domino effect.

Fanatic: A person who redoubles his effort after having lost his direction.

If you double the amount of equipment and tools in use, you must halve the failure rate simply to stay even.

Planning can be perfect - it's all theoretical. Execution can never be perfect - it involves real people using real tools on real material.

People are expected to inspect their own work, both for function and to specification… Statistical and analytical charts are maintained on the production floor by workers, not by Quality Assurance people in a remote office.

Like most computer people would have, he had stayed close to his electronic toy rather than come to the garage to watch the production operation.

The finest carver does the least cutting.

Nobody ever tried harder under pressure.

"know'why" in addition to "know-how"

Long test method names

Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch

Writing good code is hard. For lots of reasons. One reason is the tension you try to balance when choosing identifiers. On the one hand you want your identifiers to be longer to give you enough space to make them expressive. But on the other hand you want your identifiers to be shorter so they don't balloon into monsters when combined into expressions. For example:

// too short
bool is_leap_year(int y)
{
    return y % 4 == 0 && y % 100 != 0 || y % 400 == 0;
}

// too long
bool is_leap_year(int intYearValue)
{
    return intYearValue % 4 == 0 && intYearValue % 100 != 0 || intYearValue % 400 == 0;
}

// just right, said Goldilocks
bool is_leap_year(int year)
{
    return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
}

However, the names of your test methods are not subject to this design tension. The names of your test methods should never be part of a larger expression. So loosen up! Feel free to use long test method names. Names that reflect the specification not the implementation.

// not like this
static void test_leap_year()
{
    assert(!is_leap_year(1999));
}

// like this
static void years_not_divisible_by_4_are_not_leap_years()
{
    assert(!is_leap_year(1999));
    assert(!is_leap_year(2001));
}

THE Secret of Scrum

This is another fragment of the ALE conference lightning talk I did. It again follows on from Jerry Weinberg's quote:

No other observation skill may be more important to software engineering than precision listening.

I've tried to become a much better listener in recent years. An active listener. One of the things I've noticed is that software developers are somewhat prone to treat things as being black and white. True or false. Right or wrong. This is perhaps not so surprising for several reasons. Anyway, the point of the clip is not really to poke fun at Scrum, but to highlight the use of the word THE.

Precision Listening

At the ALE conference I did a lightning talk. On my first slide I quoted this from Jerry Weinberg's Quality Software Management Volume 1: Systems Thinking:

As consultants, we've found that the quickest and surest way to classify organizations into similar patterns is by the way people think and communicate.

On the second slide I quoted Jerry again (from the same book):

No other observation skill may be more important to software engineering than precision listening.

I was reminded of this a moment ago when someone cold-called me. I honestly don't remember what the person's name was or what they were selling. What I do remember is how the conversation started:

Hello, Jon Jagger speaking.

Hello, can I speak to Jon Jagger please.

Do you recognise this pattern? This response is pure waste. It does nothing but waste my time. After this response the one thing I know for sure is that they're not listening to me. And if they're not listening to me why should I listen to them?

flow = speed x density

I attended the ALE conference in Berlin last week. It was excellent in many many ways. Lots of participants have written blog entries and I thought I would write a short one about just one of the many things I thought was really great. It was the above graph which Karl Scotland drew in his talk, The Science of Kanban.

Karl used this graph in the context of traffic.

• The green line is traffic Speed and it rises (to the right) from zero at the bottom left.
• The red line is traffic Density and it rises (to the left) from zero at the bottom right.
• The black line is traffic Flow and equals Speed x Density.

Speaking to Karl afterwards we discussed the analogy:

• Speed = cycle time. The time it takes from the moment a piece of work enters the system to the time it gets to Done.
• Density = work in progress. The amount of work that has entered the system but hasn't yet got to Done.

Karl also pointed out two feedback loops.

• Start on the density line (red) at zero (bottom right) and increase the density (move up and to the left). For a while increasing the density increases the flow. Increasing the flow causes the density to reduce. Thus you have a stabilizing feedback loop helping to increase the flow.
• As you continue to increase the density you drop over the top of the flow-curve.
• Now as the density increases the flow decreases. And decreasing the flow causes the density to further increase. Thus you have a different destabilizing feedback loop helping to decrease the flow.

Simple and effective. Thank you Karl.