human factors of sleep

The following was just reported in the Harvard Business Review. The authors discussed the results in terms of how the workforce is hurting productivity, but it applies pretty generally. All of these findings can be explained easily with basic cognitive science as global fatigue of activation, particularly inhibitory connections. But we often don't account for them in design, either of products that people use when they are sleepy or work systems where employees may be sleepy.

• Stay awake longer than 18 consecutive hours and your reaction speed, memory, attention-span and decision-making all start to suffer.
• Five or six hours of sleep a night for several days in a row has a cumulative effect that magnifies these negatives.
• Throughout the waking day, humans build up a stronger and stronger drive for sleep.
• Most people can't get to sleep without some wind-down time, even if they are very tired.
• There is a transitional phase between when you wake up and the time your brain becomes fully functioning. This is why making key decisions at the crack of dawn is never a good idea.
• A person who is sleep deprived has no idea how functionally impaired he or she actually is.

Source: "Sleep Deficit: The Performance Killer," Harvard Business Review, October, 2006, Vol. 84, No. 10. Pages 53-59.

netflix movie recommendations

Netflix is offerring $1 million to anyone who can improve their system for making recommendations by 10% or more. Why is this human factors? Because Netflix's business model is based on getting people to rent many movies. If the customer already knows what movies they want, this is easy. But what happens when he/she runs out of ideas? If they stop renting, Netflix loses. So they need a way to get people to rent movies they didn't know about. Random recommendations would never work, so they need some way to predict their customers' schemas for "good movie." But everyone has a different set of attributes for this. So they need to be able to model their customers' individual schemas of "good movie" based on the limited information they collect about each one, which includes:
1. some basic demographics they collect during registration
2. a list of the movies they have renting so far and when (more recent is more relevant)
3. a list of movies they have browsed but not rented
4. lists of favorite movies or wish lists
5. ratings of movies they have seen in the past

Then they develop algorithms that can include:

1. Movies that people who liked the same movies also liked
2. Movies that people with similar demographics also liked
3. Movies that share attributes with movies that this customer liked.

If you are interested in trying to win the $1 million, let me know. I would be happy to share with you the research I have done in this area.

information architecture in the real world

Neiman Marcus just created a new boutique style store (not a web site - a real store) that is organized differently from its traditional department stores (and different from the usual model). The main difference is the information (or in this case content) organization.

Usually, department stores are organized by product. Shirts are in one place, pants in another, jewelry in another, etc. But in this new store, called CUSP, it is organized by user profile. So for the 20-something trendster, there will be all of the products that this person may want to buy: shirts, pants, suits, accessories, etc. So to check out multiple items, the person stays in the same place. This makes it easier to create matching outfits, try on items from multiple product categories etc.

Is this a great idea or what !! It shows simple attention to human factors. It significantly reduces navigation (which I would claim is even more important in a bricks and mortar store because real travel is required). And it increases the chance of impulse purchases because everything is in view, including that cute purse that would go great with the new pant suit.

But what I would really like to know is what took them so long??? Department stores have been around for decades!!!

HF of trans fat

Human factors can have a huge impact on the design of systems. Take for example how we choose the food to eat. Two years ago, no one had heard of trans fat. We happily ate oreo cookies and other baked goods oblivious to the damage we were doing to our health.

Then we learned how bad it was for us. But still, it didn't affect our eating because we didn't realize how much of it was in certain foods. So only after the nutrition labels were changed to include trans fat did behavior change. Adding it to the label made the amounts VISIBLE to the user. As soon as it did, there were huge effects. All of a sudden, companies starting making their products with no (or less) trans fat so that people would buy them. We now have trans fat free cookies, cakes, etc.

But we still get lots of trans fat in our foods - because restaurants don't have to have labels, so they can put as much in as they want. And they do. So Americans, Europeans, and most other people continue to get obese in record numbers. If we want to solve the problem, we don't need government to ban trans fat. We value our freedom of choice (trans fat isn't addictive like smoking where we have to be protected). What we need is simply good human factors design. We need the content of the foods we eat to be VISIBLE and then we can make intelligent choices all on our own.

Muslim head scarfs

This is an interesting topic for human factors. I am addressing this more as a cognitive analysis rather than a usability issue. There was an interview on NPR this morning with two teenagers who wear headscarves. They constantly were asked if wearing these scarves made them feel less free. But they replied that because it is their choice to wear the scarf, they feel more freedom. They can either wear them or not, but non-muslims only have the option not to wear them. Interesting point of view.

The reason I think this is a good human factors issue is because of the development of the schema in the girls' feelings about the scarf. I guess you can associate just about any attributes you want to an object if you have the right attitude. That shows you why optimists live longer than pessimists and satisficers live longer than maximizers.

fortune cookies

Many people are familiar with the story that buildings put mirrors in front of elevators as a way to keep people busy while waiting for the elevator to arrive. It is cheaper to do this than to speed up the elevator.

Well, I just learned that the fortune cookie was invented by a Chinese restaurant in Los Angeles to accomplish the same thing. They were served at the beginning of the meal to keep diners busy while they were waiting for their food to arrive.

It is amazing what user requirements can be accomplished through innovative design, rather than solving the most obvious problem. We can design web pages with lots of high resolution graphics as long as we force something that will keep users busy to download first and fast.

In the interest of adding our gender topic to this post, I wonder how much of this is gender-based. I have always heard that men are more impatient than women. It could also be cultural, with Americans being more impatient than Asians.

think big at business week

I love it when major business pubs have articles on human factors. Business Week is the latest (article here). The best thing is that it is short and to the point (i.e. the article is usable itself :-D).

This particular article is about Enterprise Usability (although that is my term, so they don't use it). The idea is that the whole business has to provide a good user experience, from brand image to customer service, with the actual product only being one part.

Go BWeek!!!

gaming table from Phillips

Here is a good example of a product that is predicted to attract more males than females. It is a gaming table from Philips (brief article and photos). But since I am not a gamer, I thought I should ask. Are the women out there interested in taking their board games electronic?

How is this better than the regular cardboard game? You still need to game pieces, so you have to store some physical objects. Does it add convenience? Or is it just the cool factor?

welcome HF class

Today is the first day of my undergraduate human factors course at FIU. Since I will tell them about the blog, I expect a few of them to visit between now and winter break. Please comment anytime you like (and get bonus class participation points!).

Also, I joined a research project that wants to know what people think about gender issues - specifically masculinity. I don't know much about it yet, but if anyone sees any important gender issues in the subjects I cover in the blog, feel free to comment on them.

calming fear

There was a study a saw abstracted that suggests that cartoons are better than mothers at calming childrens' fears. I thought about it for a few minutes, and it made perfect sense:

Cartoons distract the child from the fear. Basically, it activates a completely different area of the brain. If the cartoon is salient enough, it can attract all of the child's attentive capacity, thus reducing the fear to zero.

Mothers soothe the child. They assure them that the fear is not real and that they are OK. Essentially, they are inhibiting the fear and associating the current state with the "things are OK" schema. This may solve the problem, but does not eliminate the fear activation completely.

So a good cartoon will always be better than a good mother for this kind of need. As long as the fear is not based on some real-world situation that must be addressed by the child, ignorance is bliss.

expert v novice

In-N-Out Burger has a great approach to supporting expert and novices and they do it in a way that creates community as well. They have a very short/simple menu that is perfect for novices. But for experts that want something different, they have an unlisted expert menu. This also supports maximizers because they can have the exact combination they want.

What makes the community - the hidden menu has its own language. People who want to feel 'cool' can use the language so that other customers realize they are an expert customer.


From a pure human factors point of view, the hidden language has great visibility and mapping. For the basic criteria, which compose most of the customization customers will want (my prediction based on no data :-D), the customer simply provides two numbers in the format x by y. X refers to the number of burgers and y to the number of cheese slices. So you can get 5 patties and 3 slices of cheese by saying "5 by 3" Very intuitive, easy to recall, short - all the good usability principles.


But the key question is - "how does one convert from a novice to an expert. If you have friends, that would work. Or is you happen on it on Wikipedia. But in general, there is a whole bunch of service functionality that is invisible.

retrospective protocols

I just experienced a great example of why retrospective protocols are fraught with error. I was walking down the hall and asked a colleague how he was doing. I thought he said "hot" but I wasn't sure. I asked him what he said. He had no idea. He guessed that he said "I'm fine thank you." Clearly, this could not have been it - it sounds nothing like "hot."

What he did, according to retrospective protocol studies, is search his schema for a logical or typical way to answer the question, rather than his memory of what he really said. This happens a lot in retrospective protocols. Instead of reported what they were thinking at the time, users develop rational explanations that often do not correspond with reality. Often, what they were really thinking is not logical or easy to articulate. And also hard to remember, even soon after.

Cleanflicks

Wow, two in one day. Are you guys lucky!!!

I just read about a Federal Court decision that ruled against Cleanflicks et al. They are no longer allowed to edit DVDs of movies to remove the sex and violence. One of the key issues was whether the modified movies were transformative (added in value) or derivative (just different). The court found that removing content can not add value.

From a Human Factors point of view, I find these totally against everything I know. How many web sites have you improved by removing clutter, outdated content, superfluous animation or graphics, etc? The judges need a good HF course!!!!

RFID for bartenders

Sorry I have been away for so long, but I was waiting for something good to discuss. Boy did I find it.

There is a new RFID device that attaches to liquor bottles. By measuring the angle and duration of each pour, it measures how much was added to a drink. It is connected to the cash register, so it actually knows which drinks are being poured too. It can determine if bartenders are under or over pouring and it even has a warning message for consistent errors. The warning is just a beep, so they need to work on the human factors of this. But talk about instant feedback!!!!

There is some good math behind the device for those of you in doubt. It knows what the shape and size of the bottle is, so it can change its predictions based on how much has been poured from the bottle so far. And when the bottle is empty, it can recalibrate its estimates to increase accuracy even more - although this info can only be used for long term modeling of bartenders, not the immediate feedback (unless the whole bottle is poured at once).

From a HF point of view, this is cool in terms of instant feedback. To learn, telling bartender once a month that he/she overpours doesn't help. But telling him/her that he just overpoured the Creme de Menthe bottle is much more useful, because he/she can adjust the way he/she pours that particular bottle shape.
From an IE point of view, this is cool in terms of real time performance measurement and feedback - with the goal of improvement. It also adds some security because the bartender can't pour free drinks for friends (unless there is a button for that on the cash register).

I would have never thought of this one - what will they come up with next!!!

net neutrality

This topic is not centered on Human Factors, but it is something that is critically important to the development of Internet innovation so it will affect most of us in many ways.

For those of you not familiar with the basic premise, here are the two sides:

Telecoms: The fairest and most efficient way to fund the development of bandwidth is for companies that use more bandwidth to pay more for that use. So if your site has high-res graphics, video, audio, or simply lots of visitors, you will pay more for their access. A text only site with three visitors will pay the minimum. This is the basis of the free market system. And anyway, they own the bandwidth, so even if you think this is a bad idea, it is their private property on which to make such mistakes.

Internet companies: The greatest innovations of the Internet age have come about because there are minimal start-up costs to create the next greatest thing. I you think of the Web 2.0 services and other new companies (MySpace, YouTube, Skype, even Google), they were created by college students in their dorm rooms. If they had to pay for every bit, they could not have afforded to get started. And even established companies would be hesitant to create new services (think online banking) if the bandwidth used would not be covered by the extra revenue. If they charge for the new services, no one will try them out and great services will be killed at the outset.

Social organizations: It is very rare for MoveOn.org and the Christian Coalition to agree on anything, but here is one. If they (and other non-profits) had to pay for every visitor who clicks on their sites, it would kill the circulation of their ideas. Independent bloggers (especially Vloggers) would disappear. Local governments would not be able to afford to support their services. Charities would lose their online fundraising capabilities. So we need net neutrality.

And most people realize that government often screws up regulation of technology. They move too slowly to regulate something that moves so fast. Even if the regulation was good to start, technology would change and it would take 10 years for the government to update the regulation. And the regulations they do enact are generally flawed because of the influence of lobbyists, special interests, and a general ignorance of technology by the average politician.

So you are probably asking whether I am in favor of government regulation of net neutrality. To be honest, I am torn. I wish there was a free market solution. It is possible that competition in the telecom industry would create net neutrality because anyone who tried to charge more would lose business. But I don't think that there is enough competition at present to do this. So some government regulation is necessary. But how to do it, I don't know.

how much does Human Factors contribute

I was watching an interview of Alvin Toffler (the author of Revolutionary Wealth) and he said something that really struck me. His example of the problem with measuring national GDP was that when Microsoft spends millions creating a new version of Windows that is only marginally better than the old one, the measure of GDP goes up based on the money spent on it. But when thousands of programmers contribute to the development of Linux for free and thousands of companies download and use the software, again for free, there is no recognized effect on GDP.

I wondered about Human Factors in this same way. For the past few years we have been struggling to make the business case for Human Factors by proving that it increases sales, etc. But are there other effects that we are missing? I think that a usable product, even if it doesn't make me more productive at work, still makes me happier, and maybe more productive overall because of my mood. Or maybe just the happiness should be measured.

Overconfident experts

There has been a lot of writings lately about how experts are not nearly as expert as they think (Arnold Kling, James Surowiecki). The Arnold Kling article specifically discusses economists and how this overconfidence can harm public policy when governments rely on their recommendations. This is a considerable problem.

Since Human Factors has so much to say on naturalistic decision making (of which economics is a prime example), such as the fantastic research on recognition primed decision making, I think it behooves us to think about applying some our work to the public policy domain. Yes we are helping the military, law enforcement, etc., but why not macroeconomic and industrial policy at the federal level. Not only can we have a huge effect on our nation(s), but we would also increase the visibility of our field.

The Japanero Room

Another example from my stay at the conference. I had a Board meeting in the Japanero room. The hotel meeting rooms were arranged alphabetically, so the Japanero room was easy to find, right between the room beginning with 'I' and the one beginning with 'K'. A colleague asked where we were meeting. I said "the 'J' room". He had no clue what I was talking about.

This illustrates a pretty good example of how an incorrect user model can lead to a poor design. I made an incorrect assumption of his domain knowledge. Because he was a Board member, I assumed he got the same tour I did, which explained the alphabetical design (or he would have figured it out on his own by then). I also made an incorrect assumption about the quality of my message. I also assumed that saying "the 'J' room" would be enough of a semantic link to the organization of the rooms that he would understand my meaning. Because the alphabetical organization was a salient part of my schema, the statement was enough to activate it. But that is no guarantee for other users.

salient design

As I checked into my hotel to attend the IIE conference last week, I was struck by their use of Human Factors in selecting a white bedspread. I am sure that most of you have heard the nightmare stories of how disgusting hotel bedspreads are and the variety of bodily fluids that they find in stains.

So how does a white bedspread help, and why do I consider it a Human Factors application?

1. If the bedspread is white, it provides a visibly salient cue that the bedspread is clean, unlike those stories.

2. They assume that this is important to people, which implies a domain knowledge that includes those stories.

3. There is a semantic link between a clean bedspread and a holistic impression that the hotel cares about cleanliness in general, and therefore even other linens, carpets, etc may be assumed to be clean as well.

Thus, the money spent on cleaning the bedspreads, rather than hiding the stains in colorful patterns, may be worth the investment, but only if it is made clear to the user - which can be done elegantly with a white bedspread. Much better than a sign above the bed declaring that they are clean, which would just call out attention to the kinds of stains that could be present elsewhere.

customer made

I have been reading the trendwatching newsletter for just a few months, but it has become a monthly religious experience for me. It takes maybe 10 minutes to read, but I find myself clicking on lots of the links to check them out first hand, so it is more like 15-20 minutes. Not bad for such a great tool. Basically, the site identifies an emerging trend and discusses it, citing many examples. It is hard to describe briefly, so go to the site and read one or two of them for yourself. You will see what I mean.

This month's trend is "Customer-Made", discussing all of the companies that have created some way for customers to participate intimately in the design process. The companies range from high tech to simple retail and all over the world. I plan to use this as a motivator to the students in my Human Factors class to pick their own design projects in the Fall, instead of giving them one myself. It is not a trend I didn't already know about, but reading all of the ways it is being implemented was very informative and really amazed me both at how innovative the participating customers are as well as how great this is for the companies that do it.