programming and human factors
by Jeff Atwood
On a recent airplane flight, I happened to catch the movie Groundhog Day. Again.
If you aren't familiar with this classic film, the premise is simple: Bill Murray, somehow, gets stuck reliving the same day over and over.
Phil doesn't just go on one date with Rita, he goes on thousands of dates. During each date, he makes note of what she likes and responds to, and drops everything she doesn't. At the end he arrives at -- quite literally -- the perfect date. Everything that happens is the most ideal, most desirable version of all possible outcomes on that date on that particular day. Such are the luxuries afforded to a man repeating the same day forever.
This is the purest form of A/B testing imaginable. Given two choices, pick the one that "wins", and keep repeating this ad infinitum until you arrive at the ultimate, most scientifically desirable choice. Your marketing weasels would probably collapse in an ecstatic, religious fervor if they could achieve anything even remotely close to the level of perfect A/B testing depicted in Groundhog Day.
But at the end of this perfect date, something impossible happens: Rita rejects Phil.
The next time you reach for A/B testing tools, remember what happened to Phil. You can achieve a shallow local maximum with A/B testing -- but you'll never win hearts and minds. If you, or anyone on your team, is still having trouble figuring that out, well, the solution is simple.
Read more at www.codinghorror.com
Wednesday, July 28, 2010
Tuesday, July 27, 2010
I read an article on Yahoo News about the bedbug epidemic in the U.S. - a comment mentioned diatomaceous earth
as a safe, non-toxic means of killing bedbugs. So I looked up this material and found it is made up of the skeletons of diatoms and is also known as kieselgur (a name I remember that from school) and that it is so good at absorbing water that it dries up the waxy skins of bedbugs and kills them.
The list of other things that diatomite can do amazing: Read on...from en.wikipedia.org
Diatomaceous earth consists of fossilized remains of diatoms, a type of hard-shelled algae. It is used as a filtration aid, as a mild abrasive, as a mechanical insecticide, as an absorbent for liquids, as cat litter, as an activator in blood clotting studies, and as a component of dynamite. As it is also heat-resistant, it can be used as a thermal insulator.
Diatomite is also used as an insecticide, due to its physico-sorptive properties. The fine powder absorbs lipids from the waxy outer layer of insects' exoskeletons, causing them to dehydrate. Arthropods die as a result of the water pressure deficiency, based on Fick's law of diffusion. This also works against gastropods and is commonly employed in gardening to defeat slugs. However, since slugs inhabit humid environments, efficacy is very low. It is sometimes mixed with an attractant or other additives to increase its effectiveness. Medical-grade diatomite is sometimes used to de-worm both animals and humans. It is most commonly used in lieu of boric acid, and can be used to help control and eventually eliminate a cockroach infestation. This material has wide application for insect control in grain storage.
Its absorbent qualities make it useful for spill clean-up and the U.S. Centers for Disease Control recommends it to clean up toxic liquid spills. These qualities also lend themselves to use in facial masks to absorb excess oils.
It has been employed as a primary ingredient in a type of cat litter. The type of silica used in cat litter comes from freshwater sources and does not pose a significant health risk to pets or humans.
Diatomite (Celite) can be used for the removal of DNA in the presence of a highly concentrated chaotropic agent such as sodium iodide, guanidinium hydrochloride and guanidinium thiocyanate. As with other silicates, the diatomites will remove double stranded DNA but not RNA or proteins. The DNA can be extracted from the diatomites using low ionic strength buffers, including water, at neutral to slightly alkaline pH. Crude diatomites of a uniform size must first be washed in a heated acid such as 5M HCl. Calcination can further improve consistency of the material, while mild caustic treatment may improve adsorption with lower levels of chaotrophs.
The absorbent qualities of diatomite can result in a significant drying of the hands if handled without gloves. The flux-calcined form contains a highly crystalline form of silica, resulting in sharp edges. The sharpness of this version of the material makes it dangerous to breathe and a dust mask is recommended when working with it.
The type of hazard posed by inhalation depends on the form of the silica. Crystalline silica poses a serious inhalation hazard because it can cause silicosis. Amorphous silica can cause dusty lungs, but does not carry the same degree of risk as crystalline silica. Natural or dried diatomite generally contains very low percentages of crystalline silica. Diatomite produced for pool filters is treated with high heat (calcining) and a fluxing agent (soda ash), causing the formerly amorphous silicon dioxide to assume its crystalline form.
Diatomaceous earthRead more at en.wikipedia.org
By TAREK EL-TABLAWY and SINAN SALAHEDDIN, Associated Press Writers Tarek El-tablawy And Sinan Salaheddin, Associated Press Writers
BAGHDAD – The U.S. Defense Department is unable to properly account for over 95 percent of $9.1 billion in Iraqi oil money tapped by the U.S. for rebuilding the war ravaged nation, according to an audit released Tuesday.
Read more at news.yahoo.com
Tuesday, July 20, 2010
Would you have guessed there was anything like this number of wells - abandoned or otherwise - in the Gulf? from news.yahoo.com
WASHINGTON – The federal government's oil spill chief said Tuesday that seepage two miles from BP's oil cap is coming from another well, tamping down fears that leaks mean the ruptured well is unstable.
There are two wells within two miles of BP's blowout, one that has been abandoned and another that is not in production. Around 27,000 abandoned wells in the Gulf aren't checked for leaks, an Associated Press investigation showed this month.
Read more at news.yahoo.com
Monday, July 19, 2010
Plastic debris, mostly from US shores, floats in a great circle of currents north of Hawaii that is larger than t
Tamminen: 10 Environmental Disasters Worse Than BP Oil Spill
8. The Great Pacific Garbage Patch
Plastic debris, mostly from US shores, floats in a great circle of currents north of Hawaii that is larger than the state of Texas. Ten years ago, samples showed that bits of plastic outnumbered plankton by six to one. Today it is over ten to one. Fish, birds, and marine mammals mistake plastic for food and die in the thousands every month. Disposable lighters and plastic bottle caps are among the most ubiquitous culprits.
Read more at finance.yahoo.com
Saturday, July 17, 2010
Hundreds of thousands of seabirds are killed every year in European waters when they get hooked on baited lines
or caught in gillnets, The nets may be a mile and a half long and the lines may be up to 75 miles in length. So endangered species of seabirds such as albatrosses, shearwaters, petrels, fulmars, gannets, gulls, cormorants, shags, auks, divers, and grebes are being killed far out at sea - left hanging in the water to drown... Make Your Voice Heard - see the article for how to do it.from quillcards.com
Two Million Seabirds Killed In European Waters
In 1991 the United Nations Food and Agriculture Oganization adopted a plan of action for the worldwide reduction of incidental catches of seabirds in driftnets, longlines and gillnets used by fishing vessels.
A longline is a baited fishing line anything up to 75 miles (120km) in length that is let out into the water behind a fishing vessel.
A gillnet is a net hung vertically in the water behind a fishing vessel and kept vertical by floats at the top and weights at the bottom.
A driftnet is a string of gillnets tied end to end. They may be many miles long and instead of being anchored at the far end as gillnets are, they are allowed to drift with the current.
Estimated Two Million Seabirds Killed
The Royal Society For The Protection Of Birds and Birdlife International estimate that in the last ten years two million seabirds have died by being hooked on longlines or trapped in gillnets in European waters.
European Union Action
This year the European Union has issued a consultation paper that has been open for contributions since June 11th. The window within which to make contributions closes on August 9th.
You Can Add Your Voice
The European Fisheries Commission action plan initiative states:
If you wish to add your contribution, perhaps by suggesting that the recommendations of the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) be implemented straight away, you can do so by clicking on the link in the consultation paper under the section headed ‘How to submit your contribution.’
Read more at quillcards.com
Friday, July 16, 2010
The power of repetition in photography is shown incidentally in an article in the Guardian Extra today, with
three photographs that have a strong repeat pattern, from the three striped aprons in the first shot; the graphic repeat of the outstretched arms in the second shot, and the pandas ad infinitum in the third.
It is a technique that Margaret Bourk-White used many times, as in this Life magazine cover of the Hoover Dam.
Someone who has never seen a dam might still not know what one looks like from seeing this photo, but they will know that dams are big and powerful.
Tuesday, July 13, 2010
Posted by AFP on 09 Jul 2010 | Leave a comment
THE HAGUE (AFP) – The International Criminal Court has suspended Congolese militia chief Thomas Lubanga’s trial and rapped prosecutors for abusing court processes and ignoring judges’ orders.
“The prosecutor has elected to act unilaterally in the present circumstances and he declines to be ‘checked’ by the (trial) chamber,” said Thursday’s judgment suspending Lubanga’s trail which started in January 2009.
Prosecutor Luis Moreno-Ocampo’s office responded: “We will appeal in the coming days.”
Read more at ijcentral.org
Monday, July 12, 2010
The FeedBurner Status Blog
The official source for technical updates about FeedBurner within Google.
Issue:FriendFeed subscriber counts have not been reported since 10-Jul. We are in contact with FriendFeed to help resolve this issue. While publishers will a notice corresponding drop in their subscriber counts this is a reporting problem only and in no way affects feed delivery.Read more at feedburnerstatus.blogspot.com
Another time we might have stopped to look at the stalls and maybe exchanged a smile with the people standing there. This time we walked on the metro – it was getting late and we had a long journey to make to the other side of Delhi at Majnu KaTila, but that’s another story.
Now though, looking at this ‘not very good’ shot, I am transported back to the warm evening, the sounds, the sense of being there. That is why I take a camera.
Sunday, July 11, 2010
According to the National Trust, Puffin numbers on the Farne islands increased five per cent last year and increased five percent this year.
This follows a precipitous decline in 2008 when the number of breeding pairs dropped from 55,000 to 36,500.
That crash in numbers was attributed to a decline in the sand eels upon which puffins feed.
The decline in sand eels was blamed on the changing climate because sand eels have a narrow range of sea temperatures within which they can thrive.
The Farne Islands are off the Northumberland coast of England and the largest concentration of puffins in England breed there.
So why the increase in population?
Isle Of May
The large concentration of puffins in the United Kingdom is in Scotland on the Isle of May....
Thursday, July 8, 2010
On Thursday May 20, 2010 The official site of the Prime Minister’s Office set out the Conservative-Liberal Democrat coalition Government’s programme for government.
The site in turn refers to the Cabinet Office website where the full statement can be found.
There are 31 sections over 36 pages, covering topics from banking to schools, from defence to taxation.
Section 11 covers environment, food, and rural affairs, perhaps because they did not each merit a section of their own or perhaps because they are so inter-related that they were best dealt with under one heading.
In fact, the topics are in conflict. What is good for the rural economy is not always good for wildlife.
As with the other sections of the document, section 11 begins with a general statement of belief followed by the individual statements of the Governments intentions.
The general statement reads:
The Government believes that we need to protect the environment for future generations, make our economy more environmentally sustainable, and improve our quality of life and well-being. We also believe that much more needs to be done to support the farming industry, protect biodiversity and encourage sustainable food production.
I want to highlight just two of the 18 statements of intent.
Number 3 reads:
We will introduce measures to protect wildlife and promote green spaces and wildlife corridors in order to halt the loss of habitats and restore biodiversity.
Number 18 reads:
We will bring forward a motion on a free vote enabling the House of Commons to express its view on the repeal of the Hunting Act.
The Hunting Act
The Hunting Act 2004 came into force on February 18, 2005.
According the League Against Cruel Sports – a charity that has been operating since 1924, there have been 140 convictions for offences under the Act since it was introduced, with 33 convictions in 2008.
There was strong opposition to the Act from a vocal minority who supported local hunts. There was a huge voice from right across Britain in favour of a ban on fox hunting by dogs who would chase down and rip a fox apart for sport.
So why on earth has the Government stated that it is committed to letting MPs vote according to their conscience on whether to repeal an Act of Parliament that was voted on and passed just five years ago?
Critics of the Conservatives would say it is because the heart and soul of the Conservative party are the landed gentry who still believe in a divine right to rule and the right to carry on in their own backyard as they wish.
Critics would say it is because the landed gentry are living the dream of hunting with the kings of the early middle ages in the hunting preserves.
Others looking at it from the other side might say it is because the Government wants to silence the pro-hunting lobby once and for all, and a free vote will do that because ‘everyone’ knows the majority of MPs will oppose the repeal of the legislation.
Well we don’t have to analyse it. We just have to recognise that whatever the motivation behind introducing a free vote – people need to make their voices heard.
Speak loudly and insistently and people who can change things will listen.
So tell your MP. If you want a simple pro-forma letter you can send to your local MP, here it is.
You can find your MP’s contact details here at the They Work For You website.
The coalition government has published its intention to bring forward a motion on a free vote enabling the House of Commons to express its view on the repeal of the Hunting Act 2004.
I wish to register with you my opposition to the repeal of this legislation.
Sunday, July 4, 2010
Friday, July 2, 2010
July 2, 2010
Letter from Apple Regarding iPhone 4Dear iPhone 4 Users,
The iPhone 4 has been the most successful product launch in Apple’s history. It has been judged by reviewers around the world to be the best smartphone ever, and users have told us that they love it. So we were surprised when we read reports of reception problems, and we immediately began investigating them. Here is what we have learned.
To start with, gripping almost any mobile phone in certain ways will reduce its reception by 1 or more bars. This is true of iPhone 4, iPhone 3GS, as well as many Droid, Nokia and RIM phones. But some users have reported that iPhone 4 can drop 4 or 5 bars when tightly held in a way which covers the black strip in the lower left corner of the metal band. This is a far bigger drop than normal, and as a result some have accused the iPhone 4 of having a faulty antenna design.
At the same time, we continue to read articles and receive hundreds of emails from users saying that iPhone 4 reception is better than the iPhone 3GS. They are delighted. This matches our own experience and testing. What can explain all of this?
We have discovered the cause of this dramatic drop in bars, and it is both simple and surprising.
Upon investigation, we were stunned to find that the formula we use to calculate how many bars of signal strength to display is totally wrong. Our formula, in many instances, mistakenly displays 2 more bars than it should for a given signal strength. For example, we sometimes display 4 bars when we should be displaying as few as 2 bars. Users observing a drop of several bars when they grip their iPhone in a certain way are most likely in an area with very weak signal strength, but they don’t know it because we are erroneously displaying 4 or 5 bars. Their big drop in bars is because their high bars were never real in the first place.
To fix this, we are adopting AT&T’s recently recommended formula for calculating how many bars to display for a given signal strength. The real signal strength remains the same, but the iPhone’s bars will report it far more accurately, providing users a much better indication of the reception they will get in a given area. We are also making bars 1, 2 and 3 a bit taller so they will be easier to see.
We will issue a free software update within a few weeks that incorporates the corrected formula. Since this mistake has been present since the original iPhone, this software update will also be available for the iPhone 3GS and iPhone 3G.
We have gone back to our labs and retested everything, and the results are the same— the iPhone 4’s wireless performance is the best we have ever shipped. For the vast majority of users who have not been troubled by this issue, this software update will only make your bars more accurate. For those who have had concerns, we apologize for any anxiety we may have caused.
As a reminder, if you are not fully satisfied, you can return your undamaged iPhone to any Apple Retail Store or the online Apple Store within 30 days of purchase for a full refund.
We hope you love the iPhone 4 as much as we do.
Thank you for your patience and support.
NOTE TO EDITORS: For additional information visit Apple’s PR website, or call Apple's Media Helpline at (408) 974-2042.
The European Court of Human Rights has rejected the United Kingdom’s application to appeal its decision in a recent finding that stop and search powers enacted as part of anti-terrorism legislation breached human rights law.
In January 2010 the European Court held that section 44 of the Terrorism Act 2000 (the broad police power to stop and search without suspicion) violates the right to respect for private life guaranteed by Article 8 of the Convention on Human Rights (Gillan and Quinton v. UK 4158/05  ECHR 28 (12 January 2010)). The claimants received £500 each by way of compensation.-search powers ruled illegal by European court
Thursday, July 1, 2010
Just these two sites, all other sites are OK. http://www.nytimes.com/2010/06/27/magazine/27Tuna-t.html http://theonlinephotographer.typepad.com/the_online_photographer/blog_index.html