irrational optimism or statistical ambiguity???

I recent survey from Greenberg, Quinian, and Rosner found that 80% of Americans believe they will be in top half of the population in income in the next 5 years. Of course, it is impossible for 80% of the people to be in the top half, right? Is this an optimism bias where people foolishly think their prospects are better than they really are?

Maybe not. If we look at the income distribution, it is severely skewed, but still has a big mass near the mode. So if we take the mode as what the average American sees as the average, and use a +/- 20% as the precision that most people attribute to their perceptions of other peoples' income, the belief may not be incorrect. Think of the simple example where:

10% of Americans make less than $10k/year
10% make between $10k and $20k
60% make between $20k and $50k
10% make between $50k and $100k
10% make over $100k

If the typical person does not have the precision to discriminate within the $20-50 group, then anyone making more that $20k is already in the top "half." So 80% (10+10+60) are in the top half. I just made up these numbers, but you can see that any distribution with a big center would have this same effect. So maybe the average American is not as irrationally optimistic as we think (not that optimism is bad thing, of course).

customer experience v total process time

If you had a choice between faster service and a good customer experience which would you choose? Of course, it depends on how much time and how much better the experience could be. This is important because the discipline of work design looks at how to reduce total process time through lean process design, time study, and other largely quantitative techniques. The discipline of cognitive engineering looks at making activities easy and enjoyable. Companies really need to consider them both, either finding solutions that achieve both or making the compromises that best meet customer desires.

So here is my example. I was in a pharmacy, where I went to buy a gallon of milk. It had just opened, so there were very few customers in the store. I picked out the milk and looked over at the cash register and didn't see anyone. So I went to the jewelry area where there is also a register and there was a cashier. Another customer asked her if the bands on the watches were interchangeable. I was standing right behind him, clearly waiting to check out. She told him yes and then left me standing there to go into the camera developing area for a reason I do not know. If it was more time critical to do that task than spend 1-minute with me, then I accept her action. But she could have at least said something to me, instead of ignoring me completely. The amount she gained in total process time (if any) was doubtfully worth more than my decrease in customer experience.

With her gone, I looked back over at the regular cash register. I realized that there was a cashier there, but she was bending down to stock the cigarette shelf, which was behind the counter. So I walked over there to pay for my milk. I said "good morning" in a very friendly voice to attract her attention. She looked up at me with a very annoyed look on her face (as if stocking the cigarettes is so much more important to the cashier's job than checking out a customer) and slooooowly got up. Then she checked me out with such lightning speed I was truly impressed. Her hands hit the cash register buttons faster than anyone I had ever seen and the milk was double bagged before I even saw her touch it. Wow!!! But then she shoved it towards me in a way that tangled up the plastic handles so it took me 5 seconds to pick it up. By that time, another customer was waiting behind me in line and had to wait those 5 seconds. So her checking out speed was wasted by actions and attitude. It also again decreased my customer experience.

In this case, both time and experience were hurt by poor employee attitudes. And in theory, this job could have easily been designed to achieve both, by having her smile a little. But I can envision many similar examples where it would have to be one or the other.

So two lessons here. In the actual situation, I think the pharmacy should train/motivate its employees a little more on customer experience even at the expense of a little speed on cash register and bagging skills. Its not too hard. I cover this in the last month of my work design course.

In the case where experience and speed conflict, I think the pharmacy could have easily determined that in an empty store, a smile adds much more to experience - and therefore to customer loyalty and eventual profit than 5 seconds at the register (they didn't have THAT many cigarettes that she needed to use all of her slack time stocking them). I cover this in the first month of my human factors engineering course.


Thoughts???

convince yourself you are a leader

There is research showing that people of lower status or authority speak up less during discussion and have less credibility. So these people have little influence on group decisions. They internalize this too. They belief less in their own ideas and are more likely to let themselves be convinced by weak evidence.

So you need to do two things to be successful. You need to convince yourself that you are a leader. This will allow you to be more confident, speak up more, and be more willing to stick to your convictions.

Then you need to convince others you are a leader. This will cause them to listen more to you, and be more convinced by what you say. This research also shows that they will like and respect you more.

And none of this depends on the quality of your opinions or evidence. All it takes is a little confidence, both internally and externally.

Why is this fodder for a blog on Human Factors? Think about it and let me know what you come up with. Hint - there are some pretty common decision making biases that are based on confidence and perceived confidence.

Another funny cost/benefit example

This one would be funny if it weren't so dangerous. In some states, teen drivers are not allowed to have more than 1 or 2 passengers in the car. So to get around this rule, they have their friends ride in the trunk. Doing this at 5 mph to sneak into a drive-in movie is one thing, but doing it during normal driving, especially 65 mph on the highway, is very dangerous. But the teens do it because their perception of the risk is lower than the perceived benefit of transporting their friends.

So California passed a law making it illegal for anyone to ride in the trunk of a car. On its surface, it sounds like a funny law. But when you think of why they had to do it (increase the costs of this behavior), it makes perfect sense.

Looking at things differently

I am almost embarrassed to admit how much I 'live' human factors. Everything I see around me, I interpret in terms of how well it meets user needs as defined in context. So for example, when I am at the gym, they have an indoor track that has a simple rule. Users run clockwise Mon, Wed, and Fri and they run counterclockwise Tue, Thurs, and Sat. This is because running on a short loop puts a lot of pressure on the outside leg. So running different ways is better for you.

So why is the scheme MWF one way and TTS the other way? It seems that they are spreading the days around the week. If you go to the gym every day, this would be ideal. But if you look at real people, what gym schedules do you think are most common? Experts tell us that we shouldn't work out every day - it takes about 48 hours for our muscles to recover from a workout. So we should do each exercise every other day instead of consecutive days. Of course, this means that users who run on the track are probably running either MWF or TTS. So the way they designed this rule causes each person to run around the track the same way every time, exactly what the schedule is trying to prevent.

This error is caused by the gym management not thinking about how real users use their product. If you ask anyone naive to HF, they will probably go with the MWF and TTS schedules too. But when you point out the irony I describe above, they immediately realize the error. So how come the gym management never does?

Tradeoff between safety and speed

I saw a great example of how workers sacrifice their safety to save time. Why do they do this when their safety is their own, whereas their labor profits their company? It is not a pure economic decision. In general, it is just the assumption that the loss in safety is not very big (even though they are often wrong about this) and saving time is a natural human objective, even when there is little direct benefit. And there may be some benefits in terms of making the boss happy and getting good evaluations.

So here is the example that I saw: lets call it the ladder wiggle. A contractor was near the top of a 15 foot ladder leaning onto the roof of a one-story storefront. He needed to move the ladder about a foot forward to reach what he was working on. It would have taken maybe 30 seconds to climb down the ladder, move it, and then climb back up. But instead, he grabbed onto the edge of the roof to support some of his body weight, and wiggled the ladder side to side and shuffled it forward. Watching this with some fascination, I estimated about a 10% chance that the ladder (and the worker) would fall. 10% is not bad, but is it worth saving 30 seconds? Apparently, it was to him.

The cognitive process is simple. There he was on the ladder and the most direct way to move it was the ladder wiggle. Rather than a cost/benefit analysis, which would have resulted in a safer solution, he evaluated his first option, determined the risk was acceptable, and did it. As with RPD decisions, it was not a comparison of alternatives.

Human Factors is a state of mind

As usual at the end of the semester I get students who tell me that they see the world in a whole new way after taking my human factors course. They way I (and many of my colleagues) teach Human Factors really does become a perspective rather than a set of theories or tools to use at work. On the very first day, I tell them that they will not only be better designers, but also better and dealing with friends, relatives, coworkers, and significant others. They don't believe me then, but by week 4 they sure do.

Maybe I should start a religion and become a preacher instead of a teacher???

risk / safety tradeoff

We have known for a long time that many safety features do not actually make people safer because they use this opportunity to work faster/riskier/etc and thus revert to the individual's own risk tolerance (modified by external incentives such as productivity bonuses).

But there are also negative externalities to worry about. In a new study, Ian Walker at the University of Bath found that cyclists who wear helmets have a higher chance of getting hit by a car than those who do not. So does this mean that cyclists adjust to their added safety by riding more aggressively? It turns out the answer is no. The people who adjust their behavior is the driver. Drivers passing cyclists with helmets drive closer to the bike than drivers passing cyclists without helmets. So even though the biker doesn't change his/her behavior, his/her risk goes up.

An earlier study by Sam Pelzman found that drivers who wear seat belts drive more aggressively. So their risk stays the same overall. But the people around them have higher risk. So the total system risk is higher. Paradoxically, adding safety features increases total system risk.

There is not enough data to know how significant this effect is in general or whether it would really be better to get rid of some safety features to increase safety. Sounds like a good research proposal for an ambitious safety researcher.

Human Factors and biblical interpretation

I had a very interesting conversation with some students last night. Normally, I don't like to bring up religion at dinner because it tends to be an emotional topic. But one student seemed really interested in my view, so I thought I would share it with her. I was explaining that something in the brain's function likely evolved because of the needs of humans as the emerged from the African savannah.


She asked me if I believed in evolution or creation. I told her both, and the explanation is pure human factors. I believe that G-d created evolution. It makes much more sense to set in place a system of physical laws and cosmic raw materials than it does to preset each and every species of animal and plant.

So the next question of course is "Why does it say in the bible that it took six days etc?" But this is where human factors comes in. Imagine the state of human knowledge at the time that G-d was explaining the history of the world to Moses on Mt Sinai. Moses would not have understood any of it. I am sure that G-d would have loved to explain how the double helix structure of DNA leads to natural selection, but it would not have been a good use of time. So he explained in using stories in the same way that scientists explain their work to their families, or parents explain sex to young children. And then Moses told the rest of the Hebrews, who told their kids, who told their kids etc for about 1500 years before anyone wrote it down.

Given this reality, it is remarkable how many things do fit the historic record, not the several inconsistencies. When my students copy class notes from friends after they miss a class, there are huge discrepancies. I can't imagine going 1500 years without the content changing completely.

So, G-d created evolution, told Moses the story allegorically in a way he could understand, and 1500 years later, we get Adam and Eve, Noah's flood, etc. I don't see how it could be any other way.

Human Factors in Incident Investigation

For those of you who know me personally, you know that I injured my knee last weekend and may need surgery. One of the common areas of human factors consulting that I get called in for is to do incident investigation of these kind of events (usually a worker or a customer in a workplace or store) to find out what happened and why. In my case, the injury was the result of many aspects of human factors.

At the most basic level, I was injured because I stepped out of the way of another pedestrian walking down the sidewalk in downtown Boston. My foot landed half on a curb and half over the edge. I slipped straight down, cracking my kneecap and partially tearing my anterior cruciate ligament.

The abundance of HF causes are typical of the kinds of analysis I do in my consulting. Here are some examples:

The person I was avoiding was not looking where he was going. Why not? It was the day after Thanksgiving (the biggest shopping day of the year) and I was walking in one of the busiest shopping districts in Bostong. His attention was dominated by his current task (Christmas shopping) as well as the very salient sales signs in the store windown. This leaves very little attention for where he was going. And since he probably did not have much of an association beween walking down the sidewalk and risk, there was little drawing him towards looking at his path.

I noticed him just before he walked into me. So my time to make a response decision was very limited, leading to a quick decision. The initial schema activated was to step to the side because that is the most common response (having the lowest threshold for activation). Since I had no time to evaluate the quality of the decision or its risks, I simply stepped to the side. This did not allow time to look at the ground first. This led to the poor location of my step and my fall.

After the fall, my knee clearly hurt, but really only when I tried to bend it. There was no visible damage except a small scrape. Since I had experienced minor injuries many times before, some of which involved more pain than this event, I was certain that it was minor. My schema for this kind of injury is a little rest and a little ice and I would be fine in a day or two. This conclusion was further supported by the cost/benefit analysis. This response was easy and cheap and had a happy ending. Going to an emergency room to get it checked out was expensive, very time consuming, and could end up with a sad ending (bad news).

Then, confirmation bias set in. Even though the pain grew over the next few hours, I was able to attribute that to the fact that I kept walking on it and didn't have time to ice it. The swelling could be attributed to the same thing.

8 hours later, I went to the hospital. At some point, the cost of not going, plus the predominance of evidence that my first hypothesis was wrong, cause me to inhibit the hypothesis and consider others. Going to the hospital was both my only other existing schema and the recommendation of a reliable source (my brother the surgeon).

In this case, I was not trying to allocate blame or develop design solutions to prevent the class of incidents from occurring again. But if this had been such a case, I would probably have found no individually to be legally liable and perhaps recommended signs in busy retail neighborhoods reminding people to watch where they are going. The design of the signs would have to be salient to attract attention (with humor rather than fear), and change often to avoid habituation.

politics and entrepreneurship

As many of you know, I am a Director at FIU's Entrepreneurship Center. I am also a student of American political and public policy history, especially the Founding Fathers. So this topic will not surprise you as being something I am interested in.

A was watching a conference on CSPAN this weekend (yes I am a geek) and something a panelist said got me wondering. I don't remember what he said exactly or who he was (but he was a Fellow at Brookings), but it was about the challenges of the current political environment in DC. What I realized is that politics is not necessarily more hostile these days - The personal hatred between Andrew Jackson and Henry Clay of the early 1800s will hopefully never be reproduced. But the hostility is more visible to the average person because of advertising. And negative ads work (but this is a topic for another time).

What has changed is that politics has gone through the same transition as companies do - from entrepreneurial venture to corporate bureacracy. It used to be that individual politicians developed their own ideas, debated them in Congress, and could influence policy. Now, everything has to go through the committee system, get vetted by party leadership, and often only involve the party in power. Even lobbyists get politicized through initiatives like the Republican's K-Street project (where they tried to get all lobbying firms to hire only republicans or get shut out).

And so the same problems we see with large corporations are occurring with the current political parties. They can't be entrepreneurial anymore and new ideas get shut out. Large corporations are better at dealing with expected change (because of economies of scale) but much worse at dealing with rapid or unanticipated change. The same thing is happening in DC. The new world order (rising power of China, independence of Iran, etc) is beyond what our current system can deal with. But in the business world, there are openings for new ventures in most industries. The problem with politics is that it is easier to create monopolies and barriers to entry. Maybe we need a new Whig party. Ross Perot and Ralph Nader were able to play spoiler, but not much more than that. Maybe we need to change some of the rules to make it easier for new "ventures" to compete with the establishment. That could breathe some new life into the political process.

Just a thought.

the myth of the rational voter

This is a great article on its own merits, but also has a lot of Human Factors to it, especially considering that it was written by an economist.


If political bias were systematic, then politics would work. The average voter would be in the middle. But Caplan found that voters make the same mistakes, in some cases way off the middle. They significantly overestimate the amount spent on foreign aid and underestimate the amount spent on entitlements. I wonder if this is confirmation bias (their ideology wants to believe one thing and so they only focus on evidence in support of that - such as listening to partisan talk radio) or if the media misleads people by selecting stories based on salience rather than providing a full source of information.

Another finding is that expert economists have very different views than voters. They tend to be more libertarian. Caplan says this shows voters are wrong because economists are probably right. But I suspect that they are also wrong to some extent, because they trust theories that do not always hold up in the complex, naturalistic world in which we live. I am a free market guy, but I think most economists put a little too much faith in Adam Smith's invisible hand.

Interestingly, he says that voters tend to vote based on what they think is best for society, rather than what is best for themselves. This is encouraging in terms of belief in people's inherent goodness. But if most voters have no clue what is really best for society, it doesn't really help.

For example, voters are susceptible to salience bias. A great story on the news can overcome dozens of small experiences in the real world, especially when focus of the story is on the policy issue but in the real world we are just trying to get on with our lives.

This can also manifest in the effect magnitude. If 100 people lose their jobs but 30 million people save $10, it is good for the economy, but whose story is more salient on the news, the laid off retail worker or the family who saved a few bucks at Walmart?

One conclusion we can draw from all of this goes against what I have always believed (wow - Caplan changed my world view to some extent). I always thought that people should become familiar with the issues and vote for the candidate who supports those policies. But in fact, few voters really have the time to do this well. So really, we should select candidates based on their core values and trust that they will study the issues for us and make the best decisions. Then we shouldn't question them on it unless something seems really fishy.

A different Human Factors issue he talks about is that voters tend to be very confident in their judgments, even getting angry if you contradict them, when they clearly have very little evidence to support their views. He talks about how it is much easier to believe in the emotionally appealing side than the correct one (which requires studying). He uses as an example the immigration debate, where it is easier to blame "sneaky foreigners" than the laid off worker.

Also, there is very little feedback when you are wrong. When do we ever get to see a controlled study where two otherwise identical countries try different immigration policies and then analyze which one worked better? Econometricians do this, but most people don't read the results and wouldn't understand the statistics even if they did read them.

To prevent this problem, Caplan suggests putting more power in the hands of unelected officials who are experts in their field, such as the Fed and Supreme Court. This is OK as long as you are consistent. I suspect that the libertarian Caplan would not want nutritional experts deciding to limit his ability to eat trans-fat laden foods at McDonalds, even if they know better than he does that the negative health consequences outweigh the great taste and that these costs transfer to all of society in the aggregate.

Maybe we need to replace all political consultants with Human Factors practitioners. The pay would be better. At least, that is my inexpert perception :-D.

Anything can be improved with Human Factors

Shout out to one of my students for giving me this lead. I have always said that anything can be improved with human factors. Here is one I hadn't thought of.

Pronto has created a new packaging system for condoms that makes it easy to put on. I haven't tried them, so I can't attest to the truth of their claim, but I have read that much of the spread of HIV/AIDS in sub-Saharan Africa is tied to men not wanted to use condoms because they take too long to put on and are often put on backwards. So it is "ease of use" and "mapping" that cause the problems. The same goes for a lot of Western populations, although I have less sympathy for them.

Hurray for Human Factors.

Dolphin Stadium

Here is a better example of finding a customer need and satisfying it. One of the worst part of going to a live sporting event is that the lines to get food take longer than the time-outs. So if you want to eat, you either have to find someone hawking your favorite food row by row, or you have to miss some of the game.

Not anymore at Dolphin Stadium (and many others). Their new wireless Internet will include a system where you can order food and have it delivered to your seat. They have not set any delivery fee yet, but at the prices of stadium food, it can't be that much worse. This is a customer requirement that is worth some design effort !!

They are also adding a service to take pictures of the fans in their seats using the kinds of camera angles you see on TV. Is this a need too? I guess even if they get 1% of the fans, that is still thousands of sales a year. But I would rather bring my own camera.

Sony's new eBook

Here is a recent review of Sony's new eBook. Forgetting about the price issue for a moment, the biggest drawbacks of eBooks in general has always been the flexibility and readability of the hardware. If you can't read them comfortably over long periods of time (many people read books for an hour or more straight), they will not replace paper books.

So how should you test an eBook? I suspect that the reviewer at Tech Review (linked above) read it sitting in a chair in his office or home. Where do you read? Personally, I lie down on my back on my couch or on a lounge chair by the pool. And I prefer magazines and soft paperbacks so I can fold them up into smaller footprints (so I don't block the sun by the pool). If I tried to do this with an eBook, I wonder if it would be as easy to read as the reviewer found in his test?????

This is a great example of what call Activity-Based Evaluation. You always need to design realistic tasks to test a device like this. I don't know what variety of environments and postures people like to read in, but a good test will have the most common, most important, and most likely to cause problems. If Sony's eBook can be successful in all of these (and the price comes down), I would be a likely customer for them.

human factors in election news coverage

As most of you know by now, I am a big advocate of understanding what users want before designing a system so you can best meet their needs and expectations. The news coverage of this critical election sucked in this regard.

What most people wanted to know in this situation, besides the results of a particular race, is what the democrats' chances of taking the House and/or Senate were. So what we would have liked to know during the coverage is "of the races that are still too close to call, the dems need 4 out of 5 in the Senate and 3 out of 10 in the House" or something to that effect. That would help us to estimate they have a 70% chance of taking the House and a 20% chance of taking the Senate.

Instead, the news said "The democrats need to take 3 more seats from Senate Republicans and 20 more from House Republicans." But this is totally not helpful because some of those races could be easy to call (for either party), and some of the democrat encumbents could also be in close races. And we don't know how many close races are left. From this information, it is impossible to even estimate the odds. There is too much missing information.

So news guys, listen up. Think about what the viewers need and present information in a way that helps!!!

Good information supports retail usability

I haven't decided yet if this constitutes really good information or just enough to make a decision even more confusing, but this article about Hannaford Brothers grocery chain in New England brings up some interesting thoughts.

In order for consumers to make good retail decisions, we need good information. Whether we like it or not, nutritional information is important. Too many of us are obese, diabetic, and getting worse. And the current standard practice for labeling food is confusing to many. I did some research on these labels (send me an email if you want a copy) and it shows most people don't really pay attention to details and just trust a generic claim like "reduced fat" to indicate the product is healthy. This is not true.

In Hannaford's system, all important criteria (transfat, total fat, sodium, sugar, calories) must be at reasonable levels to get three stars (on a zero to three star scale). Even otherwise healthful products (V8 vegetable juice) get zero stars when something is too high (sodium). This is why it is a little confusing because for those of us who are not diabetic and don't get too much salt, V8 is very good for us. But the idea is good, because labels like "antioxidant rich" "zero fat" etc can make someone think it is a great food choice when it may not be.

So I applaud Hannaford's strategy, but maybe they need to update the implementation a little bit.

HF drives the politics of religious fundamentalism

Here is a really interesting one.

Originally, religious fundamentalism included values such as fighting poverty, creating world peace, ending hunger as well as outlawing abortion and gay marriage.

But those first few are very difficult to do, can't be done 100% or permanently.
On the other hand, outlawing abortion and gay marriage are binary laws or Supreme Court decisions. They are easier to accomplish and certainly easier to talk about in sound bites.

So abortion and gay marriage got more repetitions in ads and speeches. They therefore became stronger connections in the schema of both the population listening and the fundamentalists and politicians speaking. So eventually, these issues dominated the agenda at the virtual exclusion of the rest.

So the human factors of the process drove the setting of the fundamentalist agenda.

media effects on schema

A study by Pew found that the approval rating of the US in Turkey has been really low. At first, they hypothesized it was related to the Iraq war. But further analysis discovered that some recent very popular movies in Turkey are shoot-em-up action movies where the bad guys are Americans. This led to the lower approval ratings.

It is not surprising that media, even though we know they are fictional, can impact the affective connections of real schema. These movies were very salient because they were fun, violent, action-filled, loud, etc. So it didn't matter that they were also tagged as fictional, they can't help but influence the development of ethnic schema of Americans.

The same thing happens in the US when communities with few minorities see our movies that depict African-American and Hispanic characters as drug dealers, criminals, etc. Because the movies are salient, they are the only experience some people have with minorities, and they are repetitive (most movies do this), they strongly impact schema. It is a shame that the media have such a deleterious affect on so many people. And we do know that they are fictional, so it is hard to argue for any kind of regulation.

bias in surveys

It is easy to get the answers you want from a survey. All you have to do is write the questions to 'encourage' the answers you want. Of course, the purpose of a survey is NOT to get the answers you want, so this is more of an example of what NOT to do.

Here is a good example. This is a survey to see if the respondent has libertarian views.

Question 1a) Do you believe in free speech? Answer 1a) Of course!!!
Question 1b) Do you believe that terrorists should be able to promote hatred of the United States on college campuses and in town centers? Answer 1b) Well . . . .

Question 2a) Do you believe that the government should end corporate welfare and stop giving handouts to companies? Answer 2a) Strongly!!!
Question 2b) Do you believe the government should provide R&D support for alternative energy and other promising new technologies? Of course they should!!

As you can see, the average person would come out as a libertarian using survey a) but not in survey b).

This also shows the importance of using examples. When you use an example, the question's implication becomes much clearer. But what you have to do to ensure objectivity is to provide an example on both sides so that you don't bias the answer.