Situated Actions Lecture Summary

The idea of situated actions can seem quite simple and straight-forward. However, has very important implications for the field of HCI in a number of different areas. The goal of this lecture is to let you understand what the concept of situated actions means, and give you an appreciation for why it has been an important idea in HCI.

The researcher who introduced the idea into HCI is Lucy Suchman.

It was first put forward as a critique of the design of an expert system for a photocopier interface that was being proposed. The video to the left is from a T.V. program about the history of photocopiers. Fast-forward to 8:26 to see the demonstration of one of the first commercially available electrostatic photocopiers that we watched in class.

The demonstration continues on the second part, along with an advertisement for the first machine suitable for use in an office setting, the Xerox 914.

The third part of the program is also available on YouTube, if you are interested.

This is the context that Suchman came to work on photocopiers. The company she was working for had just released a new model of photocopier, which was supposed to be very easy to use, but people found it complicated, confusing and difficult.

The approach that was proposed by engineers at the photocopy company was to build a so called 'expert system' that would guide users through the process of making their copies. The idea was that if they could sufficiently clearly model the steps that a person needs to go through when they make a photocopy, then a lot of the usability problems would be solved.

The picture on the left is of a design for one of the screens in their expert help system. It includes an overview of where the user is in the sequence of the activity, assumptions the system has made about what the user is doing, an instruction for how to proceed, as well as a diagram of the photocopier and some graphical buttons.

Try to make as detailed a plan as you can to describe how someone would go about making a copy of lecture slides for their friends. They should make three copies of the slides, double-sided and stapled. The copies should also be in the correct order and the right way up both front and back (your friends are very fussy).

You can specify the plan however you like, but try to be as precise as you can. You can make the plan in a list format or in a diagram, whatever works the best for you.

If you think about how you use a photocopier, is it really like the way your plan is constructed? What happens for you when something goes wrong in a photocopier, like a paper jam? Do you plan for all these kinds of eventualities ahead of time, or do you deal with these sorts of things as they occur.

Suchman argues that the quest to make the photocopier able to interpret the actions of the user will never work and that there are several reasons for this.

Suchman uses the angaology of a kayaker going down white-water rapids to explain the kind of role that plans play in guiding us through our actions.

Indexicality expresses the idea that our communication and actions often depend for their meaning on a reference to things around us. A concrete example of this might be if you point to a button on a photocopier and say 'try pressing there'. The phrase and gesture indexes the button on the photocopier in a way that makes it clear what 'there' refers to.

Ad Hoc is a latin phrase which means 'for this purpose'. The idea it captures is that of actions or solutions which are taken for a specific purpose, not for the general purpose. Its relevance with respect to the idea of situated actions is that in addition to general purpose plans, a lot of our actions have this 'Ad Hoc' nature. As well as having a general idealised plan of how to use a photocopier, we must also be able to improvise actions in response to specific events - like when a paper-jam happens.

Mutual Intelligibility is another phrase that might seem rather complicated at first, but the idea is actually quite simple. It captures the idea that when we are with other people, we can understand what they are doing and they are doing and they can understand what we are doing. Mutual (two people each) Intelligibility (can understand).

Additionally, when you look at the detail of how people structure their interactions, you can see that people do a lot of work to make themselves understood to one another. Mutual Intelligibility is not something that just happens, we must work to achieve it.

The relevance of this concept for Suchman's argument about situated actions is that it is not possible to have this level of mutual intelligibility with a machine such as a photocopier.