How do Rich Snippets work?

In order to produce a Rich Snippet, Google looks at semantic markup (programming code that explains meanings) that webmasters have added to their pages, marking data that humans understand naturally so that machines can understand it also. Basic HTML has plenty of semantic markup that explains data structure, for example, the <h1> tag to denote a heading or the <p> tag to denote a paragraph.

To see a simple explanation of how more complex semantic markup works, take a look at the following:

You know that what you are looking at is a recipe. (Looks pretty good, no? If you are so tempted that you end up making the recipe, tell us in the comments whether it’s worth it.) You know that the text contains (among other things) the title of the recipe and a list of ingredients consisting of the types of ingredient and how much of each you will need.

If basic HTML is used, all a computer knows is that it is looking at a title and a list that contains numbers. It could be a recipe; it could be the inventory of a store; it could be the list of final grades for Geology 101.

More advanced semantic markup tags different parts of the page with code that “explains” to the computer what the data is referring to, and the relationship between different parts of the data. In the above example, the semantic markup would effectively tell the computer something like this:

<recipe title> Chocolate Chip Cheesecake Brownies

<list of ingredients>

<amount of ingredient>1 <measure of amount>cup <type of ingredient>shortening

<amount of ingredient>1 <measure of amount>cup <type of ingredient>brown sugar

<amount of ingredient>1/2 <measure of amount>cup <type of ingredient>white sugar

<amount of ingredient>1 <measure of amount>teaspoon <type of ingredient>vanilla extract

There are a number of existing vocabulary systems for semantic markup, enabling you to let machines understand and make connections about information on people, organizations, products, locations, events, media, and jobs, among other things (there’s even a vocabulary for recipes!). If all information was tagged, a search engine would ostensibly be able to return “all brownie recipes with no oil that are written by people who live in Oklahoma and are friends of my friends on Facebook.”

We’re not there yet. Google only visibly uses this information for its Rich Snippets, and only for reviews and for social/people profile sites, although they say that they do use the information from other markups. The two systems that Google supports are microformats and RDFa. As you may have noticed, the above mouth-watering brownie recipe does have ratings, but they do not appear in the search result snippet for that page:

as they are using a system other than microformats and RDFa.

More Rich Snippet support will be added in the future for markup that is helpful to searchers and that gains wide use among webmasters. E-Commerce sites, in particular, may be likely to benefit.

Which system should you use and how should you use it? Stay tuned for the next blog post on semantic markup and Rich Snippets! In the meantime, if you have your own opinions on the use of semantic markup, let us know in the comments below.

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How do you know whether your site will be compatible with them all?

One useful service for checking how any particular URL will display on different browsers is BrowerShots. They offer the ability (free!) to check how your URL will display on numerous different browsers, with the options to choose the screen size and color depth, as well as whether you want Java, Javascript and/or Flash enabled or disabled.

Although highly useful (especially if you don’t have all these browsers installed on your computer), oftentimes BrowserShots would time out before loading all of the screenshots I wanted to view.

In these cases, or if you want to check multiple URLs on a single domain quickly, the following are directions on how to disable Javascript and Flash in common browsers. The version in parentheses is the version that I tested the instructions on; they may well work in earlier/later versions as well – but you’ll have to try that yourself. If you have any comments or tips about other versions and/or browsers, please enlighten us all in the comments below!

Internet Explorer (8.0)

Disabling Javascript:

1. Go to the Tools menu.
2. Click on Internet Options (all the way at the bottom).
3. Click on the Security tab.
4. Click the “Custom Level” button.
5. Scroll down to where it says “Active Scripting” and click “Disable”.
6. Click OK.
7. Click Yes.
8. Click OK.

Disabling Flash:

The Toggle Flash add-on disables and re-enables any Flash banner by clicking the Toggle Flash button in your toolbar. To install and use Toggle Flash:

1. Download Toggle Flash. In order to use Toggle Flash, you must have Microsoft .NET 2.0 Framework or one of the later service packs installed.
2. Close Internet Explorer and install Toggle Flash.
3. Re-open Internet Explorer. The Toggle Flash button (a red circle with the Flash “f” symbol in the middle and a line through it) should be present in your command bar (the toolbar with the homepage button, printer button, etc.).
4. If you don’t see it, you may need to resize your command bar. Right-click on an empty space in the command bar and uncheck “Lock the Toolbars” in the pop-up menu.
5. Put your mouse over the line that appears and the cursor will change to a bi-directional arrow. Drag the line to expand the toolbar until the Toggle Flash icon appears. You can then re-lock the toolbars.
6. Click the Toggle Flash button to turn Flash off. The button will not show a depression, making it hard to know whether it really worked or not, but if you visit a site with Flash, the Flash will not display and you may receive a message telling you that you need to download the latest Flash player or a similar message.
7. In order to show the Flash, click the Toggle Flash button again and reload the page.

Mozilla Firefox (3.0.13)

Disabling Javascript:

1. Go to the Tools menu.
2. Click on Options (towards the bottom).
3. Uncheck the “Enable Javascript” box.
4. Click OK.

Disabling Flash:

The Flashblock add-on automatically disables any Flash banner, indicating its presence as a grey button that fluctuates between the Flash “f” symbol and a “play” arrow. If you click on the button, it will display the Flash. This add-on is incredibly convenient, not only for testing browser compatibility, but also for eliminating annoying Flash ads from displaying during your regular surfing of the internet.

Google Chrome (4.0.206.1 – dev version; should work on latest stable version as well)

Disabling Javascript:

1. Right-click on the Google Chrome icon found on your desktop.
2. Click on Properties.
3. Click on the Shortcuts tab.
4. In the “Target” field, where it says something to the effect of “C:\Documents and Settings\username\Local Settings\Application Data\Google\Chrome\Application\chrome.exe”, add a space and then “-disable-javascript” (without the quotes)
5. Restart Chrome.

Disabling Flash

Okay, this Flashblock works the same way as the Firefox one, but the installation is a tad more complicated than clicking “Install”. Hold on tight…

1. Go to the page containing the Flashblock user script. Copy the script into a Notepad file and save it as a text document as “Flashblock.user.js” (the name “Flashblock” is not crucial; the “.user.js” suffix is).
2. Find your Default user data folder for Chrome.

· In Windows XP, the pathway is: \Documents and Settings\username\Local Settings\Application Data\Google\Chrome\User Data\Default

· In Windows Vista the pathway is: \Users\username\AppData\Local\Google\Chrome\User Data\Default

* If you are using Explorer to find the folder, you may need to tell it to display hidden folders by going to the Tools menu, clicking “Folder Options”, clicking the “View” tab and selecting “Show hidden files and folders” (towards the bottom of the list of options).

3. Create a new folder within the Default folder entitled User Scripts.

4. Copy your Flashblock.user.js file into the User Scripts folder.

5. Right-click on the Google Chrome icon found on your desktop.

1. Click on Properties.
2. Click on the Shortcuts tab.
3. In the “Target” field, where it says something to the effect of “C:\Documents and Settings\username\Local Settings\Application Data\Google\Chrome\Application\chrome.exe”, add a space and then “–enable-user-scripts” (without the quotes – and make sure the first hyphen is doubled)
4. Restart Chrome.

Note: In order to display Flash permanently for any site, press Alt+F.

Yet another note: On Chrome, you cannot block Flash and Javascript at the same time. Putting “-disable-javascript” into the target field will disable your userscript that runs Flashblock. *sigh*

Happy browsing!

References:

www.mistered.us/tips/javascript/browsers.shtml

http://www.simplehelp.net/2008/04/07/how-to-temporarily-disable-flash-in-internet-explorer-7/

http://www.google.com/support/forum/p/Chrome/thread?tid=5e291648113cc731&hl=en

http://www.chromeplugins.org/google/chrome-plugins/block-flash-disable-most-visited-sites-7491.html

http://www.chromeplugins.org/google/chrome-talk/userscripts-chrome-7483.html

http://dev.chromium.org/getting-involved/dev-channel

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When we search for your keyword
Your site does view
Way down on the list
Rank three hundred and two

Your homepage has five versions
.html, .php
/index, /default
And the original, you see

Your links are all Java
Your navigation’s in Flash
Google has just one page of yours
Stored in its cache

Your title and description tags
Are all the same
The only keyword that refers surfers
Is your name

URLs are dynamic
Lots of errors in your code
Your homepage takes
Two minutes to load

Half your site content
Is password protected
Including “Terms of Use” –
Plagiarism, you suspected?

Your PageRank is zero
Backlinks twenty-one
But eleven from link farms
Ten from the blog of your son

Bumping your site up
Won’t be easy
And rapid acceleration
Can make one queasy

But hold on tight
And we’ll give it a go
Search Engine Overhaul
That’s SEO

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One of the most helpful ways to conduct research for these “lower search volume” keywords is to use Google Adwords. Not just the Adwords Keyword Tool – which may or may not be helpful in your case – but an actual Google Adwords campaign. By seeing how often your ads appear for the keywords you indicate, you can get a more accurate idea of how many people are searching for those keywords.

In general, when you set up an Adwords campaign, you want your ad to appear as high as possible in the search results, as long as you don’t have to pay too much. When you run a research campaign, however, you want to set your bid high enough that the ad appears, but low enough that the ad appears towards the low end of the search results (i.e. positions 7-10). This way you reduce the chances that people will click on your ad, reducing the amount of money you need to spend. You can get an idea of how high to set your maximum bid by using Adwords Traffic Estimator.

Start out by putting your keywords into the entry field, as seen above, using quotation marks if you want exact match (which you will probably choose if your keyword research is to determine which of several similar phrases people search for more). Do not choose a Max CPC, but do indicate your currency, language and country of interest.

Results:

Note that the bid amounts that are returned are enough to place the ad in positions 1-3 – not what we want for our research. Continue entering lower and lower amounts into the “Maximum CPC” field and clicking “Get New Estimates” until the Estimated Ad Positions show 7-10. See what the minimum amount is that you can enter and have it stay 7-10 (any lower will take you off the first page and severely minimize your chances of the ad showing at all, even if people do enter your keywords).

With prices like these, even if a few people do click on your ad, it won’t cost you so much – a bargain for effective keyword research. (Why Google estimates your daily expenses as $1 if they estimate 0 clicks at 6 cents apiece is a bit of a mystery… so you won’t be upset at them if you actually have to pay something?) Make sure to have a real landing page for your ad – if someone does click, you might gain a customer in addition to the information.

You now have the information you need to set up your research campaign, but these numbers are only an approximation. After your campaign is up and running, check frequently to make sure that your ads are showing, and showing in the position you want. You may need to adjust your bid up or down. Make sure – as mentioned above – that you indicate exact match for your keywords in order to get accurate information if you want to compare frequency of similar keywords (which would have a chance of appearing for each other if broad match was chosen), unless you are using Analytics filters that enable you to see exact keywords which sent visitors to your landing page.

After you have let the ads run for a significant period of time (still monitoring frequently to ensure that your campaign is running effectively), gather and analyze your data to see which keywords received the most impressions.

Happy campaigning!

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In addition, it is the title of your web page that appears as an entry in the search engine result pages, together with the description, which is the one or two line snippet that normally appears under that title in the entry.

Apropos the description, Google has recently been using longer snippets in the search results, excerpted from different places on the page where the search terms appear, for searches of 3 or more words. Page excerpts had often been used when there was no description tag or one that was irrelevant to the search terms, but now even when there is a description tag that has most of the search terms (but not all of them), it may be ignored. It has been theorized that this may reduce the importance of the description tag and place the emphasis for achieving good snippets on on-page optimization.

There is also a keywords tag that the user never sees – it is for search engine use only. The keyword tag has declined in importance for Google in recent years (it used to be that you just inserted whatever keywords you wanted to rank for and – poof! There you were! But no longer…), leaving the focus on the title and description tags.

Many content management systems give you an easy way to add and edit these tags, eliminating the need for you to know the HTML code to insert them manually. In case your system does not provide you with that convenience, the following is the coding that should be inserted into the HEAD of the web page in question.

Title tag: <title> insert title </title>

Description tag: <meta name=“description” content=”insert description”>

Keywords tag: <meta name=“keywords” content=”insert keywords separated by commas”>

What should these tags say? How can you use them to your advantage?

1) Make sure they exist

A surprising number of web pages have no title whatsoever, or have wholly unoriginal titles such as “Home” or “Blog”, or have the same title for every page on their website. The Search Engine Roundtable’s Blog commented recently on the problems this can cause, as Google might pick a title for you, and it may not be the title that you would choose. We saw this recently when the (untitled) homepage of one of our clients appeared in search results with the title “-name of company- logo”. Apparently Google decided that their logo was the most relevant thing on the page, but I doubt many searchers would agree. Additionally, if all the titles and descriptions are the same, Google might decide that the pages must not be unique and fail to index part of them.

2) Make sure they use the words searchers will use

The tags should contain your keyword(s), both for the searcher to see and to give Google a reason to put your page in the search results, so put on a thinking cap when you write them, but not your thinking cap – the thinking cap of your potential searcher. If your web page deals with koalas, don’t use “All You Ever Wanted to Know about Phascolarctos Cinereus” as your title, unless you want to attract zoologists only.

3) Make sure they sound attractive

Although you may think it’s “just semantics,” your choice of words can mean the difference between a searcher clicking on your site or moving on to the next. As my husband pointed out about our baby’s burpcloth: “It’s really just a nice way of saying ‘vomit rag’.” But we humans appreciate when things sound as sweet or as suave as possible – even when it’s a piece of fabric meant to catch regurgitated matter.

4) Make sure they sound attracting

Engage the searchers – compel them to click on your site. This especially applies to the description, where you have more text space at your disposal. Ask a question – invite the searcher to find out more. Which attracts you more? “LOW LOW Prices on Electronics on Joe’s Electronics website” or “Where can you find a digital camera for $20? An iPod for $30? Joe’s Electronics invites you to explore our website for the electronics you need”.   (See the first screenshot above for a good example.)

Two heads are better than one, and three are better than two, and four are better than… Test your titles and descriptions on others before you use them. Ask people who fit the profile of your potential searchers: what words would you search for? Which title sounds more appealing? Which description makes you want to click more? Use their feedback to create tags that will say: “You’re IT!”

Do you have a home page with an uninspiring title or description? Or with none at all? Post the website domain name in the comments, and we’ll give you a suggestion!

Thanks to you all for having been so patient, and for sticking around till we got back to writing here again. Looking forward to seeing you on our next post  (if you sign up for our RSS feed, of course!)

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• What are the goals of your business?
• What do you want your website to achieve – quantifiably?

This information should be at the tip of the tongue for anyone running a business – especially someone who is actively looking for a professional to improve the achievements of their business – but it is surprising how many people just… don’t know.

“I’m not sure…”

“I have to think about that…”

“Good questions…”

When you get a degree in education and they teach you how to write a lesson plan, one of the most important elements (in the professor’s opinion) and the most annoying (in the education student’s opinion) is the definition of goals. What should your student be able to do at the end of your lesson?

• The student will recite the times tables backwards.
• The student will identify all the nature metaphors in an unfamiliar poem.
• The student will design an experiment to test the pH of chicken soup.

“Why do I have to define goals? Why can’t I just write the lesson? Why can’t I just teach?” complains the typical education student. Some solve their discomfort and frustration by writing the lesson first and then formulating the goals. Much less annoying, and as this former education student found, much less effective.

Having a goal – a specific goal – focuses you. Knowing exactly what you want to accomplish – quantifiably – increases the accuracy of your foresight and your hindsight. You can plan more effectively before you act and analyze whether your actions were effective after the fact.

The critical connection between goal setting and achievement holds true in any area of life – from the most public to the most personal.

If I have to deliver a speech before the United States Congress, what exactly do I want them to do after I leave the room?

• The Congress will pass a resolution banning the sale of plush pink stuffed elephants.
• When approached individually, the members of Congress will be patient with termite-right-to-life lobbyists.

If I want to improve my marriage, how exactly do I want the improvement to manifest?

• My spouse and I will be able to discuss inviting so-and-so to the family get-together for ten minutes without raising our voices.
• My spouse and I will share our feelings about daily experiences at least twice a week.

Pursuing an elusive “achievement” or “improvement” without a specific goal is like going to the grocery store without a shopping list and vaguely expecting to come back and be able to prepare a gourmet meal. You may surprise yourself and succeed… or you may end up hungry. Either way, you will probably end up more satisfied in less time if you define quantifiable goals.

So don’t be the corner-cutting education student and jump into the water before you’ve charted a course. Before you start your business, before you expand your business, before you call us – or any other consultant – to improve your business, make sure you can give yourself answers:

What exactly do I want to see?

What specifically am I trying to achieve?

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I was just about to go to bed tonight (or rather, this morning!), when I received an email from my blog.

“Strange”, I thought, “I haven’t written anything for a while…”.

Then the penny dropped (or the “asimon” for those of us who lived in Israel before the days of mobile phones).

My site, www.debi-z.com (or debi-z.com, for those who can’t be bothered with the www), went live yesterday evening, so I guess that resent my latest blog posts !!

It’s taken a long time, mostly because I’ve been busy doing other things, but now it’s up and running.

So, a few thank you’s along the way: first and foremost to the formidable Rebecca Markowitz of illuminea, who was cool, calm and collected throughout the months of my changing my mind and driving her nuts, and without whom this site would not exist. Miriam Schwab, who created illuminea, and who agreed to do my site in the first place, and only once gave me a small nudge about finishing it off. Thanks to my logo go to Edna Segev, who I also drove a bit nuts getting the colour of each dot just right …., and last but not least, to my right hand lady, Aviva Blumstein, for translations, rewriting titles, descriptions, and all manner of other things.

Now, whoever said that “the enemy of good is better” is absolutely right!

So, there are loads of things that still need to be fixed here: the keyword density of some of pages is horrendous, not all the titles and descriptions are what I would like them to be, the internal link structure could be improved, there are “H1″s missing all over the place, and some of the texts could do with a major facelift. I need to add some pictures (with their accompanying “alt”s), and some videos (that’s for the future). The “noindex, nofollow” that let us work on the site without the search bots finding it, are still there (but they should all be gone by the end of the day), one of the navigation bars is not pretty, and I’m sure that quite a few of you can add to this list.

In fact, why don’t I let you all add to the list? 

Brilliant idea – you can all test the site and let me know in the comments below what else you’ve found that I need to fix.

I’ll even think up a cool prize for the person who gives me the most or best feedbacks!

So, please do let me know what you think of the site, thanks for sticking around, and looking forward to seeing you on my next post  (if you sign up for my RSS feed, of course!)

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The subject of last week’s conference was “Free and OpenSource Testing Tools”, and there were 3 presentations, together with great food, and a lot of networking.

The evening was kicked off, as usual, by the very competent Alon Linetzki, the founder of SIGiST Israel, who introduced the 3 speakers, and updated the audience with details of the 2009 summer conference, which will be held from the 29th June to 2nd July, focusing on “Adding Business Value and Increasing ROI”.

There will be 2 days of workshops followed by 2 days of track sessions. Some of the workshops and talks will include TPI, Agile Testing and Performance testing, and among the speakers will be international names, such as Andy Redwood and Mieke Gevers.

Dudu Bassa, of Sela, one of the SIGiST’s biggest supporters, made a few announcements relating to test engineers and test managers (if you are one, looking for a job, or your organization needs one, you can contact him).

Dudu also announced that Yaron Tsubery , the ITCB President, is running for Presidency of the ISTQB, and has a good chance to be elected. If he is elected, it will be a great success for Yaron himself (of course), but also a vote of confidence for the whole testing profession in Israel.

Yaron – we wish you the best of luck !!

OK, so back to last week. 

SNAP, by SAP

The first lecture was given by Asaf Saar, QA Manager at SAP, and initiator of the SAP Netweaver Automation Platform (aka SNAP). Asaf described the complexities that his team has to deal with:

• multi-site development and integration, including tests developed in many countries
• many technologies and frameworks, including frameworks for black box and white box testing, developed in house – each office having developed its own … 
• different testing techniques – manual, automation, unit testing, and API testing.
• more than 10,000 UI automation scripts, and more than 100,000 Java unit tests (we should all be so lucky!) 
• too many solutions, that can’t be synchronized
• lack of usability
• need to manage the Life Cycle  – run it all, get reports, analyse the reports, and currently each type of report sits somewhere else: XML, database, access, automation report, etc.
• all tests needed to be in the SAP test repository, 20 years old, with millions of tests from the whole world, and no API …

In short - unmanageable!

And from the unmanageable grew the idea of SNAP, which was developed by just 2 test engineers and a student over a 10-month period, in parallel to their regular work!

How did they do it?

SNAP was developed based on Visual WebGui, an open source RIA (rich internet application) development & deployment platform, atop standard .NET. Visual WebGui, from a small Israeli startup in Kfar Saba -  Gizmox - enables development & deployment of applications on the server which are then virtualized on a standard browser with no specific installation.

The development was done in C#, compiled, and out came an Ajax web application!

SNAP itself enables integration of any testing framework via API/Web services (test drivers), and is used by developers, test engineers, and integration engineers. The actual tests are run on temporarily idle PCs across the globe, from a central entry point, thus maximizing resource utilization (all QTP and other automation PCs can be configured public and used for testing).

Even though it was originally developed for the test group, the developers now run the automation tests before submitting the s/w to the test engineers. 

SNAP was presented at the SAP world conference last year, and it caused a lot of buzz, in particularraising the motivation and the positioning of the QA engineers in the organization.

Asaf, together with Guy Peled of Gizmox , also presented “Web on the Server”:  at AjaxWorld 2008 East. 

Asaf mentioned that they had fantastic cooperation with HP/Mercury (it doesn’t do any harm if your “daddy” is SAP!) – which helped them get as many licenses as they needed.

You can see a detailed description and screenshots from the Gizmox site by clicking on the screenshots below.

Altogether are very interesting and educational presentation.

AutoIT – A Free Functional Automation Tool

The next presentation was given by Meir Bar-Tal, of SOLMAR Knowledge Networks. Meir gave an in-depth talk and demo of AutoIT v3, a freeware BASIC-like scripting language designed for automating the Windows GUI and general scripting. It uses a combination of simulated keystrokes, mouse movement and window/control manipulation in order to automate tasks in a way not possible or reliable with other languages (e.g. VBScript and SendKeys). AutoIt is also very small, self-contained and will run on all versions of Windows (including Vista) out-of-the-box with no annoying “runtimes” required! 

The evolution of AutoIt

• Initially designd for PC “roll out” situations to reliably automate and configure 1000’s of PCs
• Now – used as a general purpose scripting language
• Now – supports complex expressions, user functions, loops etc.

The main features of AutoIt

• Easy to learn, Basic-like syntax
• Simulate keystrokes and mouse movements
• Manipulate windows and processes
• Interacts with all standard widow controls
• Scripts can be compiles into standalone execs
• Create GUIs
• COM support
• Regular expressions
• Directly call external DLL and Windows API functions
• Scriptable RunAs functions
• Detailed Help file with examples, and large community-based support forums
• Unicode and x64 support
• Digitally signed for peace of mind
• Works with Windows Vista’s User Account Control (UAC)

Below are a couple of AutoIT screenshots, so you can get an idea what it looks like.

AutoIt also has a community, run by Jonathan Bennett (just a kid – born in 1973) – author and copyright owner, an open community of contributors who are highly prolific and very dedicated. They release a new version every now and again – latest one was on the 24th December 2008. AutoIT has more than 26K forum users worldwide, who are very busy and active, and 2 books have been written about AutoIT.

In conclusion, AutoIT is a cost-effective solution for Web, .NET and Standard windows applications, it is limited to main windows technologies, and is best used with a proven testing automation methodology and framework. AutoIT enables maximizing ROI on automation by effective use of enterprise resources (parallel execution).

And interestingly enough, one of the other attendees at the evening said that he had heard of AutoIT a couple of years ago, but didn’t think it was much use for him and his team. After hearing Meir’s talk, he’s going to have another look.  

AllPairs and PICT – Free tools for test design optimization

Last but by no means least, the third talk was given by Michael Stahl, Senior SW Test Engineer at Intel (although Michael was careful to say that the talk actually has nothing to do with his work at Intel), and member of the ITCB Executive Board.

Michael started off by showing us the following video about the ESP (electronic stability przogram) in a car, which “Enhances driver control andhelps maintain direcctional stabiloity under all conditions. Provides the greatest benefit during critical driving situations, such as when driving on mixed surface conditions such as snow, ice or gravel.”:

[sorry all, I can't get the stupid video to embed here, so you'll have to click on the link below to see it]

Exotic-cars.info20.com – ESP – Electronic Stability Program

He then went on to list just a few of the different criteria that need to be considered in order to test an ESP system:

•  Car Weight
  • Net weight, maximum load, overweight
  • Location of the weight: front seat, back seat, trunk, roof
• Tires
  • Type, width, size
  • Condition – worn or new
  • Air pressure – nominal, too much, too little
• Driving conditions
  • Surface – asphalt, concrete, losse gravel, ice, snow, wet, flooded, wet + leaves, oil, sand, etc.!
  • Incline – up, down, flat
  • Contour – left turn, right turn, straight
  • Speed – slow, fast
  • Wind – from left, right, front, back
• Actions
  • Quiescent, brake, accelerate, down-shift, up-shift

Just combining these criteria, we get to the impossible number of 1,140,480 different test cases !! And that’s just for one car model….

This problem is known as a Combinatorical Explosion. which leads to a “Test Explosion” – more tests than you can ever (want to) run. The problem is very common in software, where you have many configuration parameters, external events, user inputs, environmental parameters, etc.

Ah… I can hear your brains clicking over. You are thinking (as Michael indeed mentioned) “my application doesn’t have this problem”. Either:

• the parameters are orthoganol (i.e. don’t affect each other), we can test each one on its own
• the combinations can be covered while testing other things (but that actually makes it more complex)
• we have enough planned iterations to cover all the combinations (can you be sure that you will be able to control combinations per iteration?)

Uh-uh. Nothing is quite so simple – you need to evaluate the risk of  using any of these strategies.

The other strategy is based on a theory by Tatsumi, and Cohen et al, which states that (bad) interaction between variables is usually between two variables, and that bugs involving interactions between three or more parameters are progressively less common. Therefore, we need to test all of the “all-pair” interactions, and add a few selected tests for specific cases.

Michael then moved on to demo two free tools:

1. Allpairs  (developed by James Bach)
2. PICT - Pairwise Independent Combinatorial Testing  (from Microsoft)

He used as an example, a “Generic Installer” with 9 different on/off configuration options, i.e. 512 test cases (2 to the power of 9).

First he demo’d All-Pairs, which gave an answer that just 8 test cases were needed to test all the pairs (instead of 512, remember?)

Next he demo’d PICT, which gave an answer of 9 test cases (also miles better than 512).

Well, this was where All-Pairs stops. It’s a great little free tool, but even James Bach agrees that it has its limitations, the main ones being that there is no logic, and it works only with pairs.

PICT on the other hand, is a bit more complicated, but much more powerful. And it’s also free   Pict has a pile of options, that help you do any of the following:

• combination order control
• randomization
• constraints ,e.g. if parameter x is “off”, then set parameter y to be “off”
• sub-models: bundle certain parameters into groups, e.g. if there are some cases you always want to test
• aliasing: when certain parameter(s) are “don’t care”, i.e. they can take a few values. It doesn’t matter which you use, but it would be nice to test all of them
• weighting: bias the “don’t care” value distribution to test more important values more than others, e.g. test Vista more than XP
• negative tests
• seeding

and it has a very good help file, so go look if there’s anything here that isn’t clear

In addition, PICT can work with more than 2 parameters. As a real-live example, Michael showed a case in which there were 6 parameters, with between 2 and 22 values per parameter:

A: 2 values, B: 5 values, C: 6, D:7, E:8 and F:22. 

The number of tests ended up being:  2 x 5 x 6 x 7 x 8 x 22 = 73,920.

In the PICT file, 1 constraint was defined, and 56 “if-then-else” equations. All pairs were checked.

The final result (i.e. number of test cases needed, instead of 73,920)???  90. That’s right, NINETY. That’s it!

OK, so this sounds to good to be true. Where’s the catch?  Well, no catch, but some risks:

• N-pairs is just another tool in your toolbox
  • It’s not guaranteed to find all the bugs
• The test quality is dependant on the input values you chose
  • Was your Equivalence Class correct>
  • Did you select the “right” representative values?
• If the output is influenced by more than 2 variables, you need a higher level than all-pairs to catch the bugs
• Blind selection of paris will miss the “interesting” or often-used combinations.
• Bach and Shroeder both say: “We believe that this technique is over promoted and poorly understood”

And not to be forgotten, in fact about ALL your tools: ” Don’t fall in love with your tool – it’s not a Silver Bullet. Apply your tester’s instiscts, and analyze the situation”.

I hope you all enjoyed this summary, and can take away something to start doing tomorrow. It would be great if you would add a comment to this post as to what testing improvement using tools YOU are going to start implementing.

And don’t forget, mark the 29th June-2nd July in your calendars, because yours truly (yes, that’s ME) will also be at SIGiST Israel 2009, giving a talk on “Test Engineers – Adding Value in Tough Economic Times”.

Until then, see you at my next post  (if you sign up for my RSS feed, of course!)

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This was just too good …

See you next time (if you sign up for my RSS feed, of course!)

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It really is a ray of sunshine in the gloom and doom of thousands of layoffs across so many sectors.

However, if you read on all the way to the bottom, then you get to this really cool post about 14 things to do if you are laid off from a tech job. 

The shortlist is below, but go and read the whole post, for the full explanations of what these things really mean, and why they are good to do (although some of them will need translating for wherever you happen to live).

1. Get involved in an open-source project
2. Go to start-up fairs
3. Get project work
4. Update your profiles
5. Learn some new skills
6. Answer some questions
7. Get a girlfriend or boyfriend
8. Campaign in a swing state
9. Take some time off
10. Move out of the Bay Area
11. Buy a new rig
12. Take pictures
13. Volunteer
14. Start your own company

I haven’t got anything else to add, except to hope that none of you really needs this list.

But if you think you might – get started now, before the guillotine drops. And in any case, do pass it on to any of your friends and family who may be in need.

If you have any other ideas to add to the 14 above, please stick them in a comment here for all my readers to see. Thanks.

It’s a short one this time. You deserve it, after all my long-winded posts (and I deserve to see my bed before 2am for a change)!    See you next time (if you sign up for my RSS feed, of course!)

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