7BOBOž·HJS$$$$$$&/ž´ÐHž¸ôž·88žÆÆ·ŒÌÌž­pÀÀÍ6äË÷Pž­pÍ6àÆÀÍ6ìËó@Í6üËòôÍ9$ž¶dž·< -Z ,ÿÿ`@6¾žÆÆ·ŒÌÌž­pÀÀÍ6äË÷Pž­pÍ6àÆÀÍ6ìËó@Í6üËòôÍ9$ž¶dÿû 8Í8žÆÆ·ŒÌÌž­pÀÀÍ6äË÷Pž­pÍ6àÆÀÍ6ìËó@Í6üËòôÍ9$ž¶dxHH ÿâÿã,6G{àHH dÿ'`ÿÿž©P †[R/±Y6ížµÔžµÐÿ,ž¶ôž·ž¶Øžµdž·¼ €íÎÍžµ@Ope6Yž¬ÀÍqú  ÿÿž·p4´ÿÿÿÿÿÿÿÿ(mkDSETRŸŸž·ž·Ðž·, ëž·`;ËÐFGÆÇ £ ¤ È [ ‰ ¯ û ü ƒ „ È É Ž ª Ï ÿ·¸ F z | · ¹ ò  » À    ¸ Á ë ò 2ž·0úž·ˆ‰Àž¶l I+ž¶ht,ž¶pExercise C: Review of a program with respect to the theory of action This exercise is for 8% of the marks, handed out 24th Feb; due before or at the start of the lecture on Thur.19th March. In that lecture I will discuss the answers, and late assignments will not get any marks. It should not take long: ideally only as long as it takes to write one or two exam questions (30-60 minutes), though of course getting it printed, and the unfamiliarity of the exercise means you will probably take longer. Still, the importance of this exercise is not the amount of time and effort but that it is designed both to consolidate the lectures on theory, and to give a feel for the exam questions on this module. The exercise mainly consists of writing a partial critique of an interface, similar to the earlier exercise (D2), but this time as well as describing each symptom in your own words, classifying it accúording to the framework given in the lectures. In other words, the idea is to produce a description of bugs and good features of the interface, each analysed for where it lies in terms of the theory described in the lectures. The best thing is to use ClarisWorks painting or drawing as the subject, and to use the notes you took in doing the core exercise. Alternatively if you don't mind starting from scratch in looking for problems, you might prefer to do a critique of Hypercard since you will now have that fresh in your mind. It is OK to discuss where the problems are with other people, but you should do your own analysis and classification. List the problems you notice, describing them first in your own terms and then try to classify them according to the framework described in lectures and handout 10: by (1) whether it is a problem of doing or perception (of the design of the commands or of the feedback), and if possible (2) the step in the theory of action; (3) on which of the aspects of userÀ experience it scores badly (EUP, learnability, or guessability); and (4) on whether it is a problem of the semantic or articulatory gulfs or neither. See the two examples of this below. Say why you think your classification is correct (or why the theory is inadequate). Some problems may really be several related problems with separate analyses (see handout 10), if the user gets stuck while doing something but that this is because some information delivery mechanism (e.g. an icon or command name) is failing to work as it should. There are 4 parts to this exercise: A. As just described, first list and classify the first 3 problems you note, not counting the ones given below as examples. Classify symptoms by: 1. ToA side (doing vs. perception) and stage. 2. Guessability / learnability / EUP. 3. Is it a problem of the semantic gulf, the articulatory gulf, or neither. B. In addition, list the two best aspects of the interface (in your opinion),+ again classifying these features in terms of the theory. C. Now apply the framework to some non-trivial task (intention) in the interface (e.g. centering a title in the page as a whole i.e. vertically as well as the usual horizontal centering) which some users might want to do sometimes, and analyse how well the interface supports that particular task in terms of the framework. D. Give one example of each of the following. Re-use the problems you have already described, or new ones as necessary from the same interface, or if you are stuck even from some other interface. a) A safety (defence) cost. b) A failure on the perceptual side. c) A large articulatory gulf on the doing side. Example 1: You can draw a straight line to an exact vertical by holding down while you originally draw it. , However if you want later to change its length, you cannot hold it to the vertical in the same way, so it may become slightly crooked. This is an articulatory failure on the doing side, and will affect EUP because learning will not make it go away (you know what you want, it is just difficult to execute it accurately). Example 2: If (in ClarisWorks v.1) you choose the Reshape command from the menus, you can edit the shape of a freehand curve you have drawn. You do this by moving the control points that appear. However it is hard to discover how to delete a control point: pressing does not work. This is a problem of guessability: impossible to guess (without reading help) but easy to learn after that. It is in the central arena, at the translation step (what is the command's "name"?).DSET|ÿÿ(Hÿÿÿÿÿÿž´ü 4–Í  ›6ÿÿ*4–ÍDSET¤ÿÿ(Hÿÿÿÿÿÿž´àÍ 56Í ›:¼6ÿÿ*4RÍDSETRP Pžµüžµž¶` ž¶¬P   Qž¶TQ IT: HCI module 1998, handout 11 (S.W.Draper, disk courses 6, Feb 1998)