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Notes for undergraduates

This has been in my email signature for the last year or so.

If you email me, please say your full name, level and, if relevant, which course(s) you are referring to. Although you know what “the lecture” or “the coursework” refers to, I may not. If you refer to an article, book or a webpage, please give the full reference and/or URL so that I know what you are talking about. Similarly, if you include a citation (surname, date) in a piece of writing, please include the full reference (in APA style) at the end.

It is important that you leave the University of Sheffield in the habit of writing formally to people. I may not be bothered by you not including an introduction to your email, or by you not signing it, but many people you write to will be. You should also make an effort to capitalise, punctuate and spell correctly in your email. Again, although I may not judge you negatively if you fail to do this, many people will, so you should practice the habit of taking care over these things when you write.

If you are a PSY241 student, please read this before emailing me

If you need a response by a particular time, it helps if you mention this in the email. If you have an urgent query (i.e. requires a response within 48 hours) email is not appropriate. Please call instead.

I do not read my email over the weekend, or after 5pm.

Answers to most of the questions I get asked are readily available, either in the Undergraduate Handbook or on the Departmental or University webpages. If you write to me with a question like this I will probably write back and ask you where you have looked already for the information. If you want to avoid this, please say in your email how you tried searching for the information you required before emailing me.

If we make an appointment to meet you must turn up on time. If you are late I may not be able to begin a meeting with you because it will infringe on other commitments. If you are unable to make an appointment, or are going to be late, please call to let me know, so that I am able to do other things with my time and am not waiting around like a lemon.

Finally, congratulations on reading this far. Here’s some good advice: “The way to get a first class mark is to answer a specific question by making arguments about theories and supporting those arguments with evidence”. Even if you aren’t aiming for a first class mark, you can still avoid getting a lower mark than you should by ensuring that you answer the question. We cannot give you marks for providing correct information which does not answer the question.

Bonus advice for 2012: If you want to get answers from busy people, ask simple direct questions. “Is today’s lecture at 12 o’clock?” is better than “When are the lectures?”, and may be more in line with what you really want to know anyway. Both of these options are better than something like “What do I need to know about the course?” which is so poorly specified that you are unlikely to get a swift and helpful answer.

Fundamentals of learning: the exploration-exploitation trade-off

The exploration-exploitation trade-off is a fundamental dilemma whenever you learn about the world by trying things out. The dilemma is between choosing what you know and getting something close to what you expect (‘exploitation’) and choosing something you aren’t sure about and possibly learning more (‘exploration’). For example, suppose you are in a restaurant and you look at the menu:

  • Fish and Chips
  • Chole Poori
  • Paneer Uttappam
  • Khara Dosa

Assuming for the sake of example that you’re not very good with Sri Lankan food, you’ve now got a choice. You can ‘exploit’ – go with the fish and chips, which will probably be alright – or you can ‘explore’ – try something you haven’t had before and see what you get. Obviously which you decide to do will depend on many things: how hungry you are, how good the restaurant reviews are, how adventurous you are, how often you reckon you’ll be coming back ..etc. What’s important is that the study of the best way to make these kinds of choices – called reinforcement learning – has shown that optimal learning requires that you to sometimes make some bad choices. This means that sometimes you have to choose to avoid the action you think will be most rewarding, and take an action which you think will be less rewarding. The rationale is that these ‘sub-optimal’ actions are necessary for your long term benefit – you need to go off track sometimes to learn more about the environment. The exploration-exploitation dilemma is really a trade-off : enjoy more now vs learn more now and enjoy later. You can’t avoid it, all you can do is position yourself somewhere along the spectrum.

Because the trade-off is fundamental we would expect to be able to see it in all learning domains, not just restaurant food choices. In work just published, we’ve been using a new task to look at how actions are learnt. Using a joystick we asked people to explore the space of all possible movements, giving them a signal when they made a particular target movement. This task – which we’re pretty keen on – gives us a lens to look at the relation between how people explore the possible movements they can make and which particular movements they learn to rely on to generate predictable outcomes (which we call ‘actions’).

Using data gathered from this task, it is possible to see the exploitation-exploration trade-off in action. With each target people get 10 attempts to try to identify the right movement to make. Obviously some successful movements will be more efficient than others, because it is possible to hit the target after going all “round the houses” first, adding lots of extraneous movements and taking longer than needed. If you had a success like this you could repeat it exactly (‘exploit’), or try and cut out some of the extraneous movement and risk missing the target (‘explore’). Obviously this refinement of action through trial and error is of critical interest to anyone who cares about how we learn skilled movements.

I calculated an average performance score for the first 50% and second 50% of attempts (basically a measure of distance travelled before hitting the target – so lower scores mean better performance). I also calculated how variable these performance scores were in the first 50% and second 50%. Normally we would expect people who perform best in the first half of a test to perform best in the second half (depressingly people who start out ahead usually stay there!). But this analysis showed up something interesting: a strong correlation between variability in the first half and performance in the second half. You can see this in the graph

This shows that people who are most inconsistent when they start to learn perform best towards the end of learning. Usually inconsistency is a bad sign, so it is somewhat surprising that it predicts better performance later on. The obvious interpretation is in terms of the exploration-exploitation trade-off. The inconsistent people are trying out more things at the beginning, learning more about what works and what doesn’t. This provides them with the foundation to perform well later on. This pattern holds when comparing across individuals, but it also holds for comparing across trials (so for the same individual, their later performance is better for targets on which they are most inconsistent on early in learning).

You can read about this, and more, in our new paper, which is open-access over at PLoS One A novel task for the investigation of action acquisition.

New paper: A novel task for the investigation of action acquisition

Our new paper, A novel task for the investigation of action acquisition, has been published in PLoS One today. The paper describes a new paradigm we’ve been using to investigate how actions are learnt.

It’s a curious fact that although psychologists have thoroughly investigated how actions are valued (i.e. how you figure out how good or bad a thing is to do), and how actions are trained (i.e. shaped and refined over time), the same effort has not gone into investigating how a behaviour is first identified and stored as a part of our repertoire. We hope this task provides a useful tool for opening up this area for investigation.

As well as the basic description of the task, the paper also contains a section outlining how the form of learning the the task makes available for inspection is different from the forms of learning made available by other ‘action learning’ tasks (such as, for example, operant conditioning tasks). In addition to serving an under-investigated area of learning research, the task also has a number of practical benefits. It is scalable in difficulty, suitable for repeated measures designs (meaning you can do it again and again – it isn’t something you learn once and then can’t be tested on any more) as well being adaptable for different species (meaning you can test humans and non-human animals on the task).

The paper is based on work done as part of the EU robotics project I’m on (‘I’M-CLeVeR‘) and on Tom Walton’s PhD thesis, The Discovery of Novel Actions

We’re hiring!

The Department of Psychology at the University of Sheffield is hiring! Due to recent departures and a forthcoming expansion we have 6 academic posts to fill, for lecturers, senior lecturers/readers and chairs. Perhaps you, or someone you know, is looking for a job or a change – here’s why you should apply to work with us:

The Department: One of the very best Psychology departments in the UK for research, consistently rated ‘excellent’ (i.e. the top score) in the Research Assessment Exercises over the last 20 years. In the last RAE the department ranked 6th in the UK in terms of Research Power (i.e., quality × quantity of research activity). We have a strong tradition of interdisciplinary research and you’d be joining at a great time to renew that tradition of cognitive science. We have smart and enthusiastic Undergraduate students, 80% of whom have AAA at a-level (ie the top grades). We have one of the largest number of postgraduate students for any UK psychology department, which includes taught masters courses (I teach on this one) and PhD students. The academic faculty are dedicated and collegiate, small enough in numbers to be friendly, large enough to be a resource for you in your research. We have one of the best staff-student ratios of any UK psychology department…All this, and you get me as a colleague

The University: Times Higher Education University of the Year 2011, and globally one of the best universities in the world. The University of Sheffield has academic departments covering all major disciplines and is a ‘research intensive University‘, meaning you wouldn’t spend all your time teaching.

The City of Sheffield. Ah, Sheffield! More parkland within the city limits than any other UK city. 7 trees for every person. The so called “largest village in England”, a city renowned for its friendliness, for its sporting links, creative industries and generally too many good things to list here. And it’s in the middle of the country, so you can get about easily – two hours from the capital, three from Bristol, four Edinburgh. And cheap – I live in a house which makes my London friends who can’t afford a flat sick with jealousy. I can walk to work, or round to friend’s houses. I’m talking quality of life here people.

So, please pass the word around that we’re looking for psychologists of all types to apply for these positions. If you want to get in touch I’m happy to talk informally to anyone who is thinking about applying. Not that I have any significant power over the hiring decision, but I’m happy to spill the beans over what we’re looking for and what the department is like. You can contact me by phone or email.

(In sad, but unrelated news, we lost our Professor of Development Psychology earlier this week. These job adverts are obviously quite separate from this sudden gap we have in Developmental Psychology and about which no plans have yet been made).

Trust in science

I’ve been listening to the CBC series (2009) “How to Think about Science” (listen here, download here). The first episode starts with Simon Schaffer, co-author of the The Leviathan and the Air Pump. Schaffer argues that scientists are believed because they organise trust well, rather than because they organise skepticism well (which is more in line with the conventional image of science). Far from questioning everything, as we are told science teaches, scientists are successful as expects because of the extended network of organisations, techniques and individuals that allows scientists, in short, to know who to trust.

Schaffer also highlights the social context of the birth of science, focussing on the need for expertise —for something to place trust in — at a time of military, political and ideological conflict. Obviously, our need for certainty is as great in current times.

Understanding of the processes of science, Schaffer asserts, is required for a true understanding of the products of science, and public understanding of both is required for an informed and empowered citizenry.

This last point puts the debate about open access scientific journals in a larger and more urgent perspective. In this view, open access is far more than a merely internal matter to academia, or even merely a simple ethical question (the public fund scientists, the publications of scientists should be free to the public). Rather, open access is foundational to the institution of trusted knowledge that science (and academia more widely) purports to be. The success of early science was in establishing the credibility of mechanisms for ‘remote witnessing’ of phenomenon. The closed-access publishing system threatens to undermine the credibility of scientific knowledge. Once you recognise that scientific knowledge is not the inviolable product of angelic virtue on the part of science, you concede that there the truth of scientific propositions is not enough — we need to take seriously the institutions of trust that allow science to be believed. The status of expert who cannot be questioned is a flattering one, but it relies on short-term cache. If we care about science and the value of scholarship more widely then open access publishing is an urgent priority.

Update: Romanian translation of this web page (by Web Geek Science)

Manipulation in Education

There is a fundamental power asymmetry in education. Teachers understand what they are teaching, learners do not. Learners, by definition, cannot have a full appreciation of what they are about to learn, of its value and of how it will change them. If they did, they would not be in the position of learners. The only way you can ignore this is if you are mislead into accepting the banking metaphor of education (education as information transmission, teachers as content providers, students as receptacles to be filled).

One implication of this power asymmetry is that the authority and responsibility of the teacher cannot be abdicated. Students should not be left to ‘decide for themselves’. Sure, students can pursue their own path of inquiry, but teachers should be there to persuade and guide them. For a teacher to pretend that they are letting students ‘make up their own minds’ is simply a denial of their role, an obfuscation. Of course it is important that people can decide for themselves, but students’ autonomy is not icreased by a lack of teacher manipulation of their choices. All our choices are conditioned by our past, our environment and by other people. Free choices are still conditioned choices.

A discussion of this in relation to the morality of manipulation is provided by Buss, S. (2005). Valuing Autonomy and Respecting Persons: Manipulation, Seduction, and the Basis of Moral Constraints. Ethics, 115(2), 195-235. doi: 10.1086/426304. Buss only touches on the topic of education in a footnote (no. 71) but the implications of the general argument for education are clear: we cannot avoid affecting other people, manipulation without informed consent of their free chocies is inevitable, and so we cannot pretend that it is possible for teachers to avoid making choices for their students, or that full informed consent of students in the content of their education is desirable or possible.

Orality and academia

Academia is a quintessentially literate culture. Studying is reading, the outputs of research are papers and books. Your are judged on your ability to express yourself in writing, and when you do this you must reference the written works of others. This is what defines scholarship. More than this, the habits of thought are patterned by literacy. Literate thought is analytic, dissective. The business of science is that of ordering into lists, breaking into parts, assigning subordinate and superordinate.

And yet there is also a non-literate part to being an academic, a part closely alighted with the praxis of the discipline. This is giving lectures, discussing in seminars, attending conferences. The paper outputs of academia can disguise this component, but it is essential.

In a high-education system dominated by production-line and consumption values, by a receptacle-model of education (students as containers, education as a substance) it is easy to denigrate the ‘live’ oral component of academia, but in doing so we deny students contact with an essential part of scholarly life. Additionally we deny ourselves a cognitive model which can augment literate thinnking.

Walter Ong (Orality and Literature, 1982/2002) has written convincingly about the psychological dynamics of oral vs literate culture. Literate culture encourages finished works, whereas the knowledge of oral cultures is always live, an act of telling rather than knowing. As such it is part of a commons, rather than copyrighted (and plagarised). Oral knowledge is situational, empathetic and participatory, rather than abstracted and objectively distanced, it is contested rather than autonomous and tends towards holism rather than the progressive analytic deconstruction of literate thought. Oral thought is thematic compared to literate thought’s ability to dictate strict chronologies and linear narratives / list structures (just think of the memory constraints on oral culture which lacks written aids to see why pure abstract lists are impossible).

It is clear that academia needs to take elements from both of sides of these distinctions. Oral cognition can be impressionistic rather than precise, conservative rather than innovative and amnesic rather the hypermnemonic. Nonetheless the lived aspects of oral thought are a vital part of disciplinary practice and exposure to them is essential if students are to get a true view of their subjects.

A similar thing is argued by Kevin McCarron, a English literature lecturer and part-time stand-up comedian who argues for the imporance of improvisation in teaching. He says that an overreliance on preparation (the script or text of the class) as getting in the way of the (living) interaction of student and teacher:

(article in the Times Higher Education)

“If we don’t put ourselves under pressure, nothing interesting or exciting is going to happen. How could it? In fact, what we’ve done is spent three hours the previous night making sure that it doesn’t happen.

“Then we have the gall to offer these hours of preparation as morally sound. Self-protection is being offered to the world as a moral value. That preparation has been done to protect the teacher from the students. Teachers spend hours and hours preparing because they are terrified of bring caught out.”

How do psychologists think?

I believe that the important thing about psychology is the habits of thought it teaches you, not the collection of facts you might learn. I teach on the psychology degree at the University of Sheffield and, sure, facts are important here — facts about experiments, about the theories which prompted them and about the conclusions which people draw from them — but more important are the skills which you acquire during the process of learning the particular set of facts. Skills like finding information and articulating yourself clearly in writing. Those two things are common to all degrees. But lately I’ve been wondering what skills are most emphasised on a psychology degree? And I’ve been thinking that the answer to this is the same as to the question ‘how do psychologists think?’. How does the typical psychologist[*] approach a problem? I’ve been making a list and this is what I’ve got so far:

1. Critical — Psychologists are skeptical, they need to be convinced by evidence that something is true. Their default is disbelief. This relates to…

2. Scholarly — Psychologists want to see references. By including references in your work you do two very important things. Firstly you acknowledge your debt to the community of scholars who have thought about the same things you are writing about, and, secondly, you allow anyone reading your work to go and check the facts for themselves.

3. Reductionist — Psychologists prefer simple explanations to complex ones. Obviously what counts as simple isn’t always straightforward, and depends on what you already believe, but in general psychologists don’t like to believe in new mental processes or phenomena if they can produce explanations using existing processes or phenomena.

I am sure there are others. One of the problems with habits of thought is that you don’t necessarily notice when you have them. Can anyone offer any suggested additions to my incoate list?

* I’m using the label ‘psychologists’ here to refer to my kind of psychologists — academic psychologists. How and if what I say applies to the other kinds of psychologists (applied, clinical, etc) I’ll leave as an exercise to the reader.

Cross-posted at