08 October, 2014

The tyranny of testing over design

There’s a great debate about processes and methodologies that are considered to be effective, but they aren’t. While plenty of blog posts, workshops, public talks celebrate the triumph of continuous testing, we seem to forget about the good old principles of design. Continuous experimentation and branding advocacy are sometimes working together to hold back not just design, but also common sense.

Experiments at Airbnb… what’s the point?

On May 2014, on Airbnb’s techy blog an article appeared called Experiments at Airbnb, where they provide useful examples of how to run split testing, alias A/B testing. They make controlled experiments — they say, that are very important in shaping the user experience on their site. The tips themselves seem to be rather sensible, but I’d be really grateful if someone could be so kind to explain to me what the practical achievements of these experiments are in terms of design.
The post illustrates two examples related to the price filter:

A feature that was rejected.
Two variations that were split tested.
Let’s now look at what has been implemented on the current site, and try to book a place for 2 nights on the current site:
As you can see, not only is the currency not there (and yes, people nowadays travel a lot and they need to see it), but even worse, the label on the price filter does not communicate whether the price is per night or per number of nights booked. That would be a legitimate question wouldn’t it? Good luck with finding the answer, the obscure label “Price Range” certainly is not there to help. You’ll have to select one of the properties to find out that the price displayed in the filter is per night. One might argue that during some (badly run?) usability testing nobody raised this issue. Or that most people would understand the meaning (arguably not), or that it’s still better than calling it just “price”, but for God’s sake, why can’t they just put a clear label where it’s needed? That’s what they do on Booking.com, or in a different way, on Way to stay:

That would be a bullet-proof way of making it work for everybody, without the need for any A/B testing or usability testing whatsoever.

The point here is, the price filter on Airbnb contains a fundamental design flaw, as a very established and quite obvious design principle is to label things properly in order to avoid misunderstandings.

This specific example clearly shows how the outcome of the split test can get invalidated by the fact that the design solution does not meet the design heuristics in the first place.
As a side note, there was no need for A/B testing to come up with very obvious conclusions such as:

  1. Why would people ever prefer a generic quantitative indicator instead of actual figures?
  2. There is no point in showing the highest price on the slider, a plus sign is enough to let people know that the top prices are higher than the displayed value, as soon as the algorithm behind is accurate enough to include only a range of prices that is statistically significant.

While focusing on these minor details, how many users chose to leave Airbnb because they could not understand clearly how much they would have to pay?

Do you really need to test that? And what if testing turns into a hurdle to design?

The second example described in the post is about the fully revamped interface that was released in July 2014:

The new design is a neat improvement, as users can now see images of the properties without loading a new page, and see the location of the properties on an interactive map. It took a long time to get there, but it looks nice. Was there any need to carry out A/B testing to confirm which design was better? As a designer I would say of course not. But let’s say that the A/B test results pointed to a drop in KPIs on the redesigned version, what would the next steps be? There are so many differences between the new and the old version that identifying the culprit would be utterly impossible. This reminds me of another similar example. In his 2012 presentation called Design for continuous experimentation, Dan McKinley, engineer at Etsy, shares the story of how continuous testing lead the design team to abandon certain design proposals, such as opening an item on a new tab or adopting endless pagination. While going through the presentation, I thought it contained a fundamental flaw. Unlike usability testing, which should also be treated with great caution, an A/B testing does not give much insight into what exactly made users prefer one version over the other. Maybe the implementation of version B was not good enough?

Whatever the reason, the main point here is aren’t we going towards a trend where testing dictates design solutions just because there’s no time during a design meeting to come up with a solution that is accurate? Are we dropping design thinking in favour of the cult of statistics?

In my experience as a designer performing plenty of usability testing sessions, most of the times I can foresee what the outcome of the testing will be, and that’s probably because I am quite good at doing what I do. Of course testing always provides useful insights on underrated issues, but I know what the heuristic and principles are and I never lose sight of them. But in many of the design-related discussions that I’ve been involved in over the years, these principles are not even taken into consideration most of the time.

Let’s go back to Airbnb. Here is the search widget on the homepage, after the major redesign they carried out recently:
On Firefox (Mac OS X)

On Chrome (Mac OS X)

See the ugly rounded corners? See how the controls are not the same height? It’s a one or two pixel difference, but enough to make it look not alright. And why cram all controls together like that?

If we look at the search results page, it gets even worse. Here is how it looks on my large screen, after I click on “More filters”:

Issues I found here, after looking at this for about a minute (from top to bottom):

  1. Under ‘Room type’, the three check boxes are too far from the text and icons they apply to, up to the point of being almost in the middle between one item and the one next to it. If at least they kept the border… but no, everything has to be flat now, because Apple did.
  2. When moving the slider on the price filter, the maximum amount updates on the right hand side instead of following the pin (where I would expect it to be), and the maximum price is not visible anymore — small details, maybe, but still…
  3. Large amounts of white space between filter labels and filter values. A boldface could be used as a better way to differentiate between headers and values.
  4. From ‘Neighbourhoods’ to ‘Host language’, the carets pointing down on the right hand side are out of alignment, and even though there could be a reason for such a choice, there’s a certain ambiguity as to whether they refer to the item on the right or to the whole category. Wouldn’t it be better to position them next to the labels?
  5. The text box on ‘Keywords’ does not align with any other element on that page.
  6. The ‘Show listings’ button is so massive that it doesn’t even look like a button, it actually scares me a bit.

Here is another screenshot that includes the map, taken during a different session on a different day. Some more points here:

  1. The buttons to zoom in/zoom out on the map are really small.
  2. No currency displayed on price range, and again, unclear “Price range” label.
  3. The ‘Options’ section features a really flashy indent overseeing a variety of picturesque font colours, and post-atomic, genetically-modified check boxes.

Want some more interaction? A small and cute help overlay opens when you click on the small question mark, but the pointer is displaced quite a bit from the icon:

By the way, you might have noticed that the currency was displayed in one of the two versions and not in the other. I wonder if this is because they were playing the multi-variance game to decide if designers should include the currency?

Price filter showing currency (and displacement of pin and number).

I had a similar issue when Google was testing two variations of search results pages on Google Images, and until they finally opted for the version where images open as inlays instead of new pages, it was a real pain if you happened to fall under the wrong user group.

The point here (despite the fact that they seem to have done a very good job with rebranding and the emotional impact of the site is quite effective) is there are so many issues that could have been addressed by just paying attention to detail, as you would expect from a site with millions of visitors. Visual design in particular requires being fastidious about the choices that are made. Alright is just not alright. You can’t limit yourself to dropping graphic assets into that slick and modern collection of widgets that you call GUI.

Let’s carry on with Airbnb. It’s hard to believe, but there is no way to sort the results. I suspect they must have done it for strategic reasons, but from a design perspective, this does not make sense to me, and I am sure that thousands if not millions of users have been swearing out loud because of this.

The old style pagination is one more burden to explore results and get what you want. Despite the fact that there’s plenty of space available, at least on my screen, if I want to jump to page number 5 I can’t, but hey, I can jump directly to page 56! And why would I ever do that, considering the listing seems to be totally random, with prices shuffling up and down without a criteria?

Conclusions, and a few notes

Designers should have the authority to lead decisions about how an interface should work and what it should look like, without a need to prove that what they say is right or wrong every time there is disagreement in the team. They are supposed to have the experience and knowledge to make the right choices.
Usability metrics, multi-variance testing and usability testing should all be adopted with great care. Continuous testing can be useful in many ways, but it should not replace informed design decisions.

27 May, 2014


The success of a business will majorly depend on the user experience guidelines that have been set in order to improve its prosperity. This is because the business must ensure the clients are not experiencing difficulty when they try to get access to whichever information or perform a certain function in the company’s interface. If you follow the paramount principles of user experience clearly, you will be sure of an increased satisfaction of users in relation to your company’s interface. 



The perfect place to place a form label in is above the fields, according to a study carried out. Too many people place forms on the left of part of the field, thus, creating a layout of 2 columns. This may seem appealing, but on the other hand, it is difficult to use. The reason behind this is because the form is usually vertically oriented, thus, users fill them from top to bottom. It would be easier to follow the label downwards than is sideways. 

2. Have Clearly Displayed Faces

On a Web page, the user will normally focus on people’s eyes and faces, which should be a great way to attract the attention of many users. Another interesting aspect is that users focus on the direction of the face, that is, where the person on the image is looking at. If the face is looking sideways, the user will also change directions and be less interested. Always consider a clear face image that faces at the user directly to draw more attention.

3. The Design Quality

The quality of the design is a clear sign of the web’s credibility. Like the saying, user will judge the ‘book’ by its ‘cover’. Your Book (website) will determine on how people will be attracted to its cover (design). Aspects like the typography, layout, color, consistency and style will determine how the users will notice and judge your website. The images you display will also determine majorly. Ensure everything, including the images are relevant to your audience. 

4. Avoid too Much Scrolling

Most of the users do not like too much scrolling. Studies show that around 70% of the visitors will not scroll down your page, all they do is view the content in the visible part on the screen. For that reason, always keep your principal content on the upper fold of your page. Nevertheless, don’t jut pile all the content in the above page fold because over-crowding content can also keep users bored. The name of the website and what will benefit the users should be placed on the main page and upper fold.

5. Let Your Links Be Blue

It’s good to be unique when you are designing your business website, nevertheless, it is important to follow the user experience guidelines. This is because people tend to follow the same process they used in another website to get to a certain destination. They also expect that something should be default, things like link colors, the website’s logo location and others. The link color should be darker or lighter than the background color. They should also be different from the rest of the text. Research shows that a blue link is easier to view and use than other colors. This is because many people are used to blue links.

6. The Best Search Box Should be 27 Characters wide

Some people tend to use shorter search boxes, which only display a section of a long inputted text in the box. It is recommended that you employ a search box of 27 characters, which according to the study, contained around 90% of the searched queries. You can set the width using Ms and not just points and pixels. A wider search box is better than a shorter one and has many advantages.

7. White Space Enhances More Understanding

A lot of web designers understand how important white space is, that is the space between pictures, paragraphs or buttons in the page. The space between items shows the relationship between the two and the items can be grouped by either increasing or reducing the spaces. The white space also enhances the readability of content, therefore, utilize them well. 

8. The User Testing Should Be Short Enough

A study showed that best number of tests that users carry out should be short enough, to increase the feedback positivity. If the test is extra detailed, there are chances that most of your website problems will be indicated in the tests. Always stick to none or just a single test for your users.

9. An Educational Product Page Is An Added Advantage

If you have a product page website, many people will surf through them, nevertheless, there are some sites that lack enough information on the products being sold. This is bad since the information on the products will lure customers more than just a product with prices and contact information. The information should also be easy to read and educational enough.

10. Avoid Too Much Advertising

Evidently, many people hate destructions and some are just not attracted to that extra flashy stuff. If you have a website that is flocked with ads of all sorts of banners and flash images, it will actually chase away your users. Users also tend to ignore anything that looks like an ad, therefore, as you design your website, consider the user viewpoint. 


Generally, as you are trying to design your website to be captivating enough, always remember that it is not a photograph that you will hang on your wall at home or a profile picture that you wouldn’t mind whom it pleases. A web page should be captivating and in addition to that, it should focus on the user. If you put too much stuff, it may be difficult to follow, if you put too little, it may be so cheap and empty, always be informative in whatever you post in your site. These user experience guidelines should help you come up with an eye-catching website that will satisfy your user and make them always want to visit again for another time.

22 May, 2014

Building User Confidence with User Experience (UX) Design

Increasing user confidence online is a constant challenge that both website owners and entrepreneurs face. With the prevalence of scams and frauds in the online community, creating an environment where users feel comfortable interacting, using and buying from a website is essential. User Experience (UX) design is an essential step towards building user confidence and increasing both sales and your user base. (Lead image source: Intel Free Press)

Make it Easy

Website owners have less time than ever to impress and entice potential customers to learn more about their site. While some insist that tech savvy users require different interfaces than casual Internet users, a frustrating design is still a frustrating design. Users of varying technical abilities want a system that works smoothly and seamlessly.
Creating a site that is intuitive for new users but complex enough to engage experienced users is a difficult tightrope to walk. Facebook is a textbook example of how a user friendly website can become unfriendly and unresponsive to new users through continual updates. What was once a very easy to navigate site is now covered in strange icons, making it nearly impossible to navigate paths to gather information. On the other hand, sites like Reddit and Gmail have continually worked to gather new users while increasing the usability and utility of the site for experienced users. Rather than making the sites more complicated to engage seasoned users, both sites expanded on the base options to make their sites more immersive instead. Users want to feel engaged and confident in site navigation, regardless of experience.

Using user experience to build user confidence doesn’t just encourage users to become frequent visitors and customers of the interface, it also gives them the confidence to recommend the system to others. Regardless of the features, a site that is difficult to use will never become the go-to recommendation for anyone other than hardcore users. Use user experience design to ensure both seasoned and new users feel comfortable in their ability to gather information and use the site properly.

Provide Clear Information

Internet users are warier than ever about disclosing personal information and data. With widespread data breaches in personal email accounts and state governments alike, being transparent with user information and accessibility to that information is imperative for building user trust. Luckily for us, finding a balance between User Experience and Security is possible.

Providing a disclosure policy on a website that is easy to find provides users with a degree of trust. Rather than digging through fine print or scouring the site’s policies, this transparency and openness with the distribution (or lack thereof) of data contributes to user confidence in both the developer and the site. Sites like Zappos even go so far as to disclose their privacy policy and safeguards against consumer identity theft on a separate ‘Shop with Confidence’ page to assure customers of their online safety before they put a single item in their cart. Clear information boosts the credibility of websites – something which is essential especially in e-commerce.

Prioritize User Testing

It’s said that the closer you are to a project, the harder it is to view it objectively. UX is no different. User confidence is reliant on a working system. Often, users don’t blame the system for their troubles, they blame themselves. A poorly executed error message will have users reassessing their own use rather than blaming coding errors. These users will become frustrated and ultimately leave the site entirely, never realizing a quick email or call to the company could yield the desired results.

Even more damaging is when users associate a site or interface with computer crashes or consistent errors. While small hiccups in programming may seem innocuous, they degrade any trust or respectability in a site to a regular online user, losing sales and users. Consistent error messages or an inability to use the features of a site send a red flag to users. This alerts them that the developers didn’t care enough to present a completed project, creating a breach of trust when disclosing new data.

User testing is by far the best and easiest way to ensure users are getting a positive experience. While a developer may never think to enter a symbol into a search function, a user with limited online experience may accidentally do just that, alerting developers to a flaw in the usability. This testing ensures that users of all abilities can successfully navigate the site.

Pay Attention to the Details

Often, high arching goals like creating a smooth interface or providing clear sight lines cause developers to lose sight of the basics. No matter how quickly a site loads or how nicely it is laid out, a site riddled with spelling errors or broken buttons will stand out for all the wrong reasons. Simple spelling mistakes drastically undermine user confidence in the business, product or site and lead to a decrease in sales and use. According to eConsultancy, up to 18% of revenue can be put at risk due to website errors. This impact on the bottom line makes attention to detail a first priority when developing a positive user experience.

While user testing may unearth some missed details, a full appraisal of a site and its content is important before going live. Whether it’s hiring a full-time editor or a part-time auditor for content error, catching and preventing these nuanced mistakes that crush user confidence is pivotal. Large online retailers may be able to absorb or overcome misspelled descriptions or broken links, but a smaller website simply doesn’t have the clout or proven track record to risk disclosing personal information. Double and triple checking content and site usability is a simple way to increase user confidence, no redesign necessary.

In Conclusion

UX doesn’t just create a pretty way for users to see and interact with a website. It provides an invaluable service for businesses by providing an attractive and respectable platform that encourages use, sells product sand gathers customer information. Creating a user experience bent towards improving user confidence in the brand, business or website enhances the user experience while strengthening the business it represents.

20 May, 2014


For the past few years we’ve experienced a steady lean toward minimalist design of digital space. As new technologies, such as higher screen resolutions and faster networks, influence the aesthetics of digital surface, our decisions in choosing the right approach for designing mobile interfaces will further shape user interactions and behaviors.

Living the flat world

Flat design is based on the principal of: “focusing on simplicity and clarity to ease functionality and emphasize usability”. Popularity of flat user interfaces (UI) emerged recently with Windows metro style and iOS 7. In a series of minimalist trends that rose during the past couple of years, 2014 seems to be the year that Flat UI will mature and become even more ubiquitous.

The basic influence of this approach on the graphical user interface (GUI) was the departure from skeuomorphism and elimination of gradients, shadows, textures, reflections and beveled edges. With all these limitations, the question is raised: how is dimension or depth implemented in flat UI design?

The answer goes back to the original principal of Flat design: embracing the strength of digital interface. In Flat design, depth is simulated with the combination of two main qualities:

1. Interactions such as parallax scrolling and behavior-learning responses
2. Visual clarity such as contrast in monochromatic themes, minimal use of colors, big font and less text, use of spaces and blocks instead of lines, and blurring backgrounds

Flat Icons (TriplAgent) are quick to design, scale well and blend with any visual design theme.
Sherpa, a personal assistant app that learns user habits, behaviors, and provides information that is of interest to the user.
Monochromatic or minimal use of colors (Univit) along with use of blocks and spaces instead of lines make the tap zones very clear to the user while providing a good look.
Blurred background used to set context and draws the user’s attention to focused content.

Making BIG impressions

Today, capturing a moment is a tap away. Quality photos are everywhere and taste in aesthetics is changed to own the accessible, resulting in more pleasing images on apps and mobile websites.

Higher-screen resolutions brought the affordance to go big on fonts and images. With new technologies designers are able to play more with contrast and crisp visual effects.

Last year we saw the design of websites gravitate towards single-page websites, full-screen images, and HTML video streams on landing pages, similar to Nike’s Jordan website. These designs aim to make a big first impression upon website arrival. Carrying over the same effects to mobile platforms is challenging, but doing so becomes imperative as the use of responsive design becomes more common. As a result, this year we will experience a smooth translation of same effects on mobile platforms where we’ll see more of:

Full-screen quality photo backgrounds
Big fonts as well as combinations of font sizes and font types
Single-page apps and sites that focus most user interaction on one screen
A mobile-first design sensibility (more on mobile-first & responsive design)

Big fonts and font combinations
Full screen photos (Bloom*) with condensed navigation menu
Single Pages (Nike Training Club)

Designing for short attention spans

Aside from games and other long engagement programs, mobile applications are mostly used for performing a series of quick and straightforward tasks, similar to the Move app that tracks daily activity. That pushes the interface to:

1. Learn user behavior, predict and suggest the relevant content when it is needed and where it is appropriate.
2. Communicate the content visually with hierarchy so that the user spends the least amount of time possible in locating and performing a task.
A good example of communicating with a visual hierarchy is the concept of cards, which was introduced last year by Google Now. Even though the concept had been used before with window “live tiles” or in print magazines’ feature stories, popular apps like Evernote or Pinterest use a similar concept today. Cards design enables apps to provide separate, well-designed snippets of information or interactions for their users. Big photos catch their attention, while brief texts confirm that the interaction would interest the users and tapping the cards would engage them with more detail. Scanning content feels more relaxed as it appears more intuitive and in line with user behavior as opposed to purposeful searching of web content.
Cards design (Evernote)

Cards design (Google Now)

The 2014 design aesthetic is about embracing minimalism beyond the surface aspect of user interface. It also involves designing for user interactions and optimizing those interactions visually and behaviorally to emphasize the functionality of the digital space in mobile platforms.

As brands grow their mobile presence, the bar is raised for both aesthetics presentation and user experience of the mobile interface. It is important for businesses to evolve the mobile experience to meet expectations and crucial to keep an eye on how these trends develop.

11 February, 2014

Psychology of rewards in web design

Rewards is a mechanism for telling users that they have done well – that their actions have been judged favorably.

There are two fundamental types of reward schedules which fundamentally change how rewards are experienced: fixed- and variable reward schedules.

Fixed rewards

Fixed rewards are given out at a set time, amount, and type and are opposed to variable rewards, which feel more like random rewards.

In computer games, fixed rewards are given out when you complete a level or achieve some other kind of clearly defined goal. Variable rewards are usually given out when killing monsters.

In web applications fixed rewards are the most commonly used type of reward as they provide clear goals for users to strive for. At Hacker News, features such as voting on comments, or changing template colors are unlocked as you collect Karma points for your activities. At Stackoverflow.com, you receive a badge as you engage more and more in the community. Both provide clear set goals that users can strive for in order to climb up the ladder of status in the community.

The right reward at the right time and amount

Everyone likes to be told they are doing a good job, but it is essential for rewards to work that they are given out at the right time, in the right amount, and that it is the right rewards that is being given. Ask these questions for each opportune moment to determine what is right1:

  • What rewards is the system giving at the moment? Can it give out others as well?
  • Are users excited when they get rewards or bored by them? Why is this?
  • Do users understand the rewards they are given? Getting a reward you don’t understand is like getting no reward at all.
  • Are rewards given out on a too regular schedule? Can they be given out in a more variable way?
  • How are rewards related to one another? Is there a way that they can be connected?
  • How are the rewards of the system building? Too fast? Too slow? Or just right?

There is only one way to find out the right balance of time, amount, and kind of reward: through trial and error. Balancing rewards is often a question of “good enough”1.

In behaviorism, the rate or probability of a behavior (“response”) is tried increased through stimulus (e.g. candy). The quality, or response strength, is assessed by measuring frequency, duration, latency, and accuracy2.

Positive and negative rewards (and punishments)

There are two ways to strengthen behavior through rewards: bring pleasure or excuse from pain – positive or negative rewards (also called reinforcements). Opposite of rewards are punishments3.

Positive rewards and punishments introduce stimuli to modify behavior where negative rewards and punishments take away stimuli to modify behavior. Rewards increase possibility of behavior while punishments decrease possibility of behavior.

Primary and secondary rewards

A secondary reward are the stimuli we have come to associate with the primary reward. When we see the message number notification appear on facebook, we associate that number with the feeling of receiving a message from our friends, which is the primary reward.

Variable rewards

Use variable rewards rather than fixed rewards when there is a chance that users will get acclimated to rewards the more they receive them1.

The activity level of users is a function of how soon they expect a reward to be given. The more certain they are that something good or interesting will happen soon, the more activity they will produce. When users know a reward is a long way off, the motivation is low and so is user activity4. This reward schedule is called a fixed one, as users are rewarded again and again with a fixed ratio or interval. Variable ratios and intervals on the other hand randomize rewards around an average. The latter produce the highest activity in users.

Read on to find out what variable reward ratios are and how they are different to fixed ratios and intervals.

Why variable rewards work

As humans, and animals, we react differently to certain patterns of rewards. Behaviorism has studies these patterns4 and have come to the conclusion that variable reward schedules and contingencies motivate us more than fixed schedules and contingencies.

Contingencies are rules or sets of rules defining when rewards are given out. There are two fundamental sort of contingencies: ratios and intervals. Ratios schedules provide a reward after a certain amount of actions have been carried out – the more you do, the more you get. Interval schedules provide a reward after a certain amount of time has passed.

Fixed vs variable ratios

Rewards with a fixed ratio are given out again and again after completing the same action the same amount of times. It could be that you will receive 10 karma points every 5th time you reply to a comment or that you would increase your level every 10th time you uploaded a video.

The problem with fixed ratios is that users distinctly pause completing actions when they receive a reward, as they know receiving a new reward will take a while. This creates an opportune moment for the user to walk away. However, the break in rewards caused by fixed reward ratios might also give the user an opportunity to explore different aspects the system.

Variable ratios are rewarded after a specific number of actions have been carried out, but that number changes every time. A user might know to upload approximately 10 videos to rise in levels, but the precise number is randomly generated every time – everything has a chance of reward. Such variable ratios have proven to stimulate more activity than fixed ratios – even when on average the same amount of rewards are given out.

Variable ratios are free from the pause in activity generated from fixed ratios. It’s important to note that users do not know how many actions are required this time, just the average number from previous experience4.

Rewarding with fixed ratios produces a pause in activity after a reward has been given and a burst of activity just before being rewarded. While users typically respond at a higher rate in the fixed ratios bursts, variable reward ratios provide a more consistent rate free from pauses of the fixed ratios.

Fixed vs variable intervals

Instead of providing a reward after a certain number of actions has been completed, interval schedules provide rewards after a certain amount of time has passed. Users being rewarded in fixed intervals will pause activity once an award has been given and wander around for a while. They will return frequently to check if their reward has been “refilled” or has reappeared. Gradually, checks will become more frequent as the proper time nears.

Vimeo.com utilizes fixed reward intervals for its regular users, who are allowed to upload only 500 mb of video every week. After the fixed interval of one week, the user’s upload quota is refilled. As users reach their upload quota on vimeo.com, their activity will pause until its refilled next week. Vimeo hopes users will use the pause to consider buying a pro account with no upload quota.

With variable reward intervals, the period of time changes after each reward as with the variable ratios. As with variable ratios, variable intervals also produce a steady and continuous flow of activity – there is always a reason to be active.

Example: Lomography.com

Lomography.com sells retro analogue cameras on their website and in physical stores. To spark the enthusiasm of their lomographic society (fans taking pictures with lomography cameras), Lomography has created an online community for sharing pictures.

Community activity is backed by a “piggie bank” system where users can earn piggie points by having their photos selected as “photo of the day”, by submitting reviews of cameras and accessories, by winning rumbles and competitions, by translating content, and much more. Piggie points, which have an expiration date, can be used in the online shop to by cameras and thus translate into cold cash. The piggie bank system utilizes a mix of fixed and variables ratios and intervals.

At the retro camera company, Lomography, you can earn “piggie points” for your online activity, which translates to cold cash in the lomography online store. Piggy point rewards are given out both at fixed ratios and at variable intervals.

What else?

Variable and fixed ratios and intervals can successfully be combined. Say that you need to upload 20 videos to become an elite member, where after you will have the chance of picking up a free pro-membership appearing at variable intervals.


Extinction is what happens when you stop providing a reward and will feel as a punishment that cause anger and frustration in the user. Behavior learned on the variable schedules are much harder to extinguish, as users will never know if what they are experiencing is just an unusually long run of misses and that next reward will justify their patience.


The principle of avoidance uses the negative reward of decay, pain, or other forms of punishment to keep users active. An example could be to force users to revisit your site and log in once a week to avoid their “elite” status to be taken away.


  1. Jesse Schell, “The Art of Game Design – A Book of Lenses”, Carnegie Mellon University
  2. Reinforcement at Wikipedia.org
  3. Psychology is fun at gamasutra.com
  4. Behavioral Game Design at Gamasutra.com
  5. Only a game by Chris Bateman