Usability Notes - by Chris Baker

web usage statistics, and Dr Seuss

When they were younger, both my kids were fans of Dr Seuss's Sleep Book (as I was in my turn). Among the delights for a small bed-time reader, Dr Seuss provides real time statistics about the number of people currently asleep, and (like a good statistics provider) publishes his methodology:

"We find out how many, we learn the amount,

By an Audio-Telly-o-Tally-o Count.

On a mountain, halfway between Reno and Rome,

We have a machine in a plexiglass dome

Which listens and looks into everyone's home.

And whenever is sees a new sleeper go flop,

It jiggles and lets a new Biggel-Ball drop.

Our chap counts these ballls as they plup in a cup,

And that's how we know who is down and who's up."

There's also a wonderfully goofy illustration of the machine, and I think it was this, rather than any predestination to work on usage statistics that made this one of my favourite parts of the book when I was a child.

In the real world, web usage statistics sometimes seem to offer the power (and intrusion) of the Audio-Telly-o-Tally-o Count, only to snatch it away again, and offer subtly different statistics, with various caveats.

As an example, suppose you own a website, and understandably want to know "how many visits did people make to my site in the last week?"

If you had an Audio-Telly-o-Tally-o Count, your "chap" would magically listen and look into everyone's home or ofice, find people actually visiting the site ...and then all that remains is to count the Biggel-Balls.

Of course, that's not what a usage stats tool does.

When someone requests a page from your website, their browser sends one or more requests to your website's "webserver" to send the text, images and other content that the customer needs to view the page. Along with that request comes some information about the customer's computer - its IP address, operating system, screen size, and some information about the kind of browser the customer is using. It also often tells us the URL of the page the customer came from. The webserver can record all this (in a file called a "server log") along with the time of the request, for analysis later.  This combination of facts is fairly unique to the computer - think of it perhaps as being like a footprint. When the customer requests the next page, all this happens again, creating a further "footprint". As the customer visits further pages, his or her computer creates a series of further "footprints" - the process of following their visit for analysis purposes is a bit like following a trail of footprints down a beach.

For competeness here I should say that not all analysis runs from server logs. In a popular alternative the webserver includes a small program with each webpage that the customer's browser runs when it assembles the page. The "small program" (used for example by Google Analytics) causes a message to be sent out to a log file for analysis later. And there are other methods. For the purposes of the discussion here, it comes to much the same thing.

As another aside, it is of course sometimes possible to requre every user to log in, and then to follow their individually-identified activity with a cookie. That provides more detailed information, but is not always desirable (in some circumstances requiring people to log in makes them go away instead; not everyone will accept cookies, and so on).

Pushing on with the "footprints on the beach" analogy, it's worth noting that we have a science ficton or fantasy beach here - trails can suddenly start as if someone was teleported in by futuristic technology or magic (e.g. the customer came in from a bookmark, or typed the URL of our page rather than following a link that we can detect). Similarly, trails of footprints almost always suddenly stop (e.g. the customer stopped using their browser, or went to another site). The way the Internet works means that customers don't have to do anything formally to leave your site; they just stop requesting pages.

Imagine now  a detective following these following these trails of footprints around on the beach. How do the clues compare with the Audio-Telly-o-Tally-o Count?

The detective has the following problems:

1. "Footprints" are fairly unique to a given computer, but not completely so. If Big Corporation Inc. has bought a batch of identical computers and successfully forbids its staff from customizing them in any way, then all the computers will have identical footrprints. The detective may struggle to sort out all those size 42 Converse Sneakers. The usual counting rule is to count all this as one user (technically one "unique browser") whereas the the Audio-Telly-o-Tally-o Count can magicallly see several people, and so drops several Biggel-Balls.
2. The Audio-Telly-o-Tally-o Count magically sees exactly where people stop using your website and do something else - and where they are still on the website, but not requesting pages. The detective only has the observation that the footprints stopped (the standard is to declare that a user session has ended if there are no more page requests for 30 minutes). Clearly this is arbitrary - the Audio-Telly-o-Tally-o Count might know that the user is still avidly reading a long web page, has broken off to answer the phone etc. So we might get one Biggel-Ball, as opposed to counting a new session each time there is a 30-minute gap.
3. The detective is counting "footprints" of a computer, not the people behind it. So imagine a public library which has one computer, on which people come and go all day, many of them looking at your website. The Audio-Telly-o-Tally-o Count magicallly follows this, counting the people coming and going. The detective, following computer-generated "footprints" does not know that a different human is now filling those shoes. If there's a 30-minute break, of course the detective assumes this is a new session, but if the queue at the computer is moving swiftly enough, then this won't happen often, and several different humans will be counted as one visit.
4. The Audio-Telly-o-Tally-o Count magically watches as a user switches from their desktop PC to their laptop or mobile device, or their computer at home, and can tell that this is one human continuing his or her visit. But each of these devices has a different footprint for the detective - the trainers suddenly stop, and a pair of heels carry on down the beach. So (unless the customer identifies themselves, e.g. by logging in) the detective counts a new visit each time the user switches device.

So, since we do not have an Audio-Telly-o-Tally-o Count, we can't count "visits" exactly in the common-sense meaning of the term. We can count "unique browsers" and "sessions" and combine those into a "visit" - a statistic which has some sources of error, but at least the major sources of error are known and the statistic is captured by a known and reproducible method. Note that the methodology is such that errors will usually result in under-counting:  probably better for the business and its advertisers than getting an inflated idea of the traffic. It's currently the best that can be done, not due to the limitations of your usage analytics tool or usage analytics people, but due to problems with what you can actually measure, and the decisions you have to make to interpret this.

That takes us into the realm of the many things where "I don't see why we can't just..." meets "It's a bit more complicated than that" . But that needs a whole new blog post.

So this time I think the last word belongs to Dr Seuss, and his observation ("One Fish, Two Fish, Red Fish, Blue Fish") that:

"Every day from here to there,

Funny things are everywhere."

 

Facebook - the problem of the customer being the product

Have been reading a good review of Facebook's prospects, in the Financial Times.Several interesting points (and data about the company here), but I particularly liked the following:

Facebook aims to harvest information about users and use that as a basis for ever more targeted advertising: "But the issue is whether what Facebook does to increase the value of the data it collects makes users enjoy Facebook less and use it less. Users might start to think they are the product not the customer. Not a fun feeling." [my italics]

The article points out a contrast between Facebook and Google here: if I Google for "catering services for weddings" or "Ford body repairs", its reasonably likely that I have an immediate commercial intention, and some adverts along with the search results may not be too creepy. Whereas someone posting to Facebook that they just got engaged,  or that some idiot just rear-ended their car is spreading news to friends: quite a different situation.

The Prioritizing Grid - as a project tool

When deciding requirements for a project, we're often trying to decide priorities between many items. This rapidly becomes difficult to do in your head ("or in your heads" in a meeting). Here's a useful tool, the prioritizing grid.

It originally comes, I think, from Richard N Bolles, author of "What Color is your Parachute" (a manual for job-hunters and career changers). Career counsellor and consultant Beverly Ryle has an interactive version on her website. The original purpose is to rank skills that a person has (e.g. "I am good at writing and also at cooking, particle physics and  kung-fu, but which of these do I like doing best?"). In its original context it is part of an exercise to help identify careers that a person is likely to find they'd enjoy. But the system could be used for prioritizing any kind of things - here is a screenshot of it in use to prioritize features of interest when choosing a car.

The way it works is that you write out the things you want to prioritize in any order, and number them 1-10 (if there should happen to be 10). In the screenshot, the un-prioritized items are listed on the left. Then you work through them in pairs like this:

• Which do I prefer, 1 or 2?
• Which do I prefer, 1 or 3?
• Which do I prefer, 1 or 4?

Once done with number 1, you do the same  with 2:

• Which do I prefer, 2 or 3?
• Which do I prefer , 2 or 4?

and then you move onto number 3:

• Which do I prefer, 3 or 4?
• Which do I prefer, 3 or 5?

...and then with each of the other factors until you reach the last pair.

It sounds cumbersome, but actually does not take at all long, unless you are over-thinking it, or need to define the factors better, or have a lot of items that you don't care about much.

Once you're done, you go through each  factor and you count up the number of times you preferred it to something else. This gives you the rank order.

In the screenshot example I've done that (the website has pairs of radio buttons to indicate your choice, but you could of course do this on a piece of paper....). On the right of the screenshot you see the priority order that this generates. It looks like I want a car that seats 4 passengers, has plenty of boot ("trunk" to US readers) space, is cheap on fuel and hard to steal (family life in Oxford...).  

As with anything else, I'd say "don't let the tool take over". Perhaps you don't really have a preference between a pair, or can't answer until  the items are better defined. Either of those discoveries could be useful - probably more useful than forcing everything artificially into neat priorities in order just to get the worksheet done.

Why you might not want to "Friend" me on Facebook

Recently I had an exchange with a work colleague about Facebook - she'd seen me listed as "People you may know", and I'd seen here there too. A new etiquette issue of our times is whether "friending" someone on Facebook means crossing over from their professional life into their personal one, and whether that is an issue for them.  So neither of us had yet clicked the "Friending button". This is to do with my earlier theme of how Facebook and the like can break down the Chinese walls we like to have in our lives.

Some people mix their work and leisure circles freely on Facebook an its equivalents, others like to keep things separate. You can't tell before clicking "Friend" which camp this particular person is in (unless a person has set their Facebook privacy so that everyone can see what they do there, and there are good reasons you might not want to do that) .

My own practice is that LinkedIn, Twitter and this blog are where I publish my professional life, whereas my Facebook posts are about my hobbies, sometimes about my family, and about my sense of humour. Judged from my facebook account, I do not work at all: at least I rarely if ever discuss it.

That creates a stream that I don't mind people from my professional life seeing, but that I recognize will be utterly uninteresting to many of them. So I tend not to friend. It is not that there is anything on Facebook that professional colleagues should not see. I assume that posting on Facebook is Publishing - there is every chance that current or future clients will get to see it, so it is not the place for innermost secrets. But I don't want to bore. My professional and facebook networks DO overlap of course, but either with people who have "friended" me (I'm unlikely to turn down anyone I really know) or where I know, from non-work time with people (watercooler, lunches, pub etc.) that they aren't likely to mind exposure to my leisure interests.Or sene of humour. I don't see Facebook as an Inner Circle to which only special colleagues get promoted, just a different circle of people with a high tollerance of my leisure interests.

(Speaking of Circles, I am on that too, but have yet to take the time to understand it. Until then, I'm keeping quiet on it).

So - if you are a professional colleague of mine, see me as a "person you might know" on Facebook and are wondering whether to "friend" perhaps this will help you decide. If you are wondering why I don't "friend" you, this is probably the answer (i.e. nothing personal).

Google, Facebook, the mixed blessings of better-organized data

Google is consolidating it's Policies, and Facebook is continuing to roll out the new Timeline. Both developments could be seen as aiming to organize data better and so make things more convenient. Which sounds great, until you read things like:

"If you haven’t been keeping up with how Timeline will change your Facebook experience, then you are in for one heck of a surprise. As ReadWriteWeb so aptly states, “Timeline turns the profile into an illustrated, browsable history of a user’s entire life, with major milestones and little moments smartly chosen by Facebook’s algorithm.”

Prior to timeline, Facebook stalkers would have to manually sort through pages and pages of wall postings to find out the personal details of your Facebook activity. Timeline drastically simplifies this process."

From Facecrooks (a blog which monitors scams and nuisances that appear on Facebook)

And:

"By combining the wealth of personal data it already holds, Google is enhancing its ability to run targeted ads which allows it to compete with Facebook, which already shows ads based on a users’ interaction with brands.

For example, the blog post says Google will now be able to “provide reminders that you’re going to be late for a meeting based on your location, your calendar and an understanding of what the traffic is like that day.”

Not all users will be comfortable letting Google take such control over their lives, despite its claims that it is trying to “help you by sharing more of your information.”

Econsultancy; "New Google privacy policy shares user data across multiple products"

The theme is that better-organized data might not be "better" from the customers' point of view. Or at least might have a downside.

Apart from worrying about stalkers or Big Brother watching you, another hazard is the way that joining up the information can accidentally break down the Chinese walls that many people like to have in their lives. For example, Chris Nuttall, writing the in Financial Times, tasks of finding that his daughter is accidentally sending him a live feed of a photo shoot she was doing for a class project. Meanwhile, he's listening to Spotify and accidentally streaming a list of music he is hearing to his Facebook profile. ("Happily, I had been displaying my usual good taste in tunes, rather than indulging in the occasional guilty pleasures of 1970s prog rock."). Similarly, you could have your feed trumpeting "I just bought [insert item chosen for wife's birthday here] at Amazon". She might no longer be surprized. 

An important thing here is that the need for privacy is contextual in a subtle way - you might usually be fine with Amazon boasting of your custom, but not for presents. You might be usually fine with your network knowing what music you are listening to, but not if you're kindly allowing your kid sister to use your computer and she's on a Hannah Montana binge. You might be fine with Facebook "knowing" you're gay (i.e. this being pretty easily inferred from your "likes" and posts) but you might prefer that to be none of your work colleagues' business.

Note added 29 Jan 2012: The Onion just covered much the same ground, but satirically: "Google Responds To Privacy Concerns With Unsettlingly Specific Apology"

Pet hates - automated jollity

One for the Pet Hates series. It's become fashionable to be a bit wacky or  matey in marketing communications to customers. But this is a bit risky, as you don't know what mood thery're in.

So in this example, the response email to an order I placed tells me how excited the autoresponder is to get my business (blue ring in the image below). "It's all rather exciting, isn't it?", burbles the autoresponder. Thrilled to the core of its little processors, it is, no doubt. So obviously very false. Harmless enough, perhaps, but I'm really not in the mood for this kind of thing right now, so it comes over  irritating.

In an "oops - it could so easily happen to you" item, I'm addressed as "Dear Other Baker" (arrowed red  in the image). Probably not because they have a customer called Baker already. More likely because the puldown for the title field did not have the choice of "Dr". (I applied for a credit card when I'd recently got my PhD, put "Dr" onthe form thinking that might help, and am stuck with it now...) A bit surprising perhaps that the Title pulldown does not accommodate "Dr", but it's not a design failure: the "Other" value in that title  pulldown opens up a field in which unanticipated titles can be entered. There are of course very many possible titles that humans adopt (Brigadeer, Captain, Princess, Guru...), and some people are very particular about being allowed to use the correct title.  So a free text field is arguably better than some humungous pulldown of all known options: if you truly wish to be addressed as "Jedi Master" on the delivery  label of your goods, then the free text field can accommodate your wish. So the design is sensible, but it looks like something went wrong in populating the field from the value I gave.

Alternatively the company thinks I am one of the Others, a race of creatures from the "Song of Fire and Ice" fantasy series by George R R Martin (appeared on TV as "Game of Thrones". But this seems unlikely, as I have never knowingly killed anyone with a crystal sword and then magically re-animated them as zombie servants.

Nice usability ideas - Glooo contact form

So here's the opposite to the "Pet Hates" series - ideas that I see in use and think are neat.

Glooo.co.uk  would be happy if you filled their contact form (assuming you want to contact them about something sensible, I suppose). But people don't like filling out contact forms. So Glooo head their form with a  big bold statement "Less than 2% of visitors will fill in the form below". We all would like to be in the top 2% (ideally in the Wall Street sense, perhaps, but you've got to start somewhere....). My guess is that it works, and in any case it is amusing...

Usability pet hates - secret password rules

Pet usability hate number one - sites that have restrictions on password choice, but don't tell you what the restrictions are. In this case I invented a nice secure password, entered it twice and then was told on submission that the site only does weaker passwords. I don't believe that using special characters is so outrageously unusual as to be something the designers shouldn't have anticipated! Sometime you also see secret rules that passwords must be a minimum length. I think it would be better if any such rules were either unnecessary (so that customers can be protected by the strongest passwords that would work for them), or at least explained before data entry!

Can't say this is the number one hate in terms of things I hate MOST, it's just the first one to come along. Maybe I'll find more "Pet hates" over time. I'm not going to provide links to the sites in question - I don't want to join the "nyah, nyah, ne nyah, nyah your site is rubbish" school of usability writing.

Sorry, no hard and fast rules in UX

"People want me to give hard and fast rules: don't show more than X menu items; don't write more than Y words per page; nothing should be more than Z clicks from the homepage. Sadly, UI design doesn't work that way. Usability questions seldom have a single answer. Rather, they are qualitative issues that specify the direction and nature of inevitable design tradeoffs."

Jakob Nielsen, as part of a post about the additional challenges of usability for mobile devices (my italics).

How long will users stay on your web page?

The received wisdom is that users don't hang around long on a web page, so you'd better get it to load quickly and then capture their attention immediately.

Some recent research by Liu et al, and discussed in an article by Jakob Nielsen, offers some more insight (and a big statistical study to back these up).  As you'd expect, users make a quick decision - in maybe 10 secs or less - and then move on or stay. The longer they stay, the more likely they are to stay some more: the probability of them leaving drops pretty exponentially.

Statistically, the pattern follows The Weibull Hazard Function, a concept from reliability engineering. The pattern follows a "negative aging distribution". You would get the same results by asking "how likely is a given component in a machine to fail" when the quality of the components is highly variable (so that, the longer this particular component has been reliable, the more likely that it is one of the good ones off the line and will keep functioning). If the manufacturer had better QA in this hardware example, then the componets would begin to follow a "positive aging function" instead - they are all as well made as each other, and so the probability of failure simply rises over time due to wear and tear.