Talk:Steering law

"bird's eye" view

Currently the article refers to a "bird's eye view of the tunnel" which makes little sense in terms of idiomatic English. That idiom refers to what a sharp-eyed hawk could see flying high above the Earth - it does not have the same meaning as "top down" view or "God's eye" view (or even "fifty thousand foot" view, which implies a lack of clarity). A bird flying high above a tunnel sees only the entrance and exit points! It would be better to avoid idioms like these all together, since they are essentially slang and quite likely to confuse anyone who doesn't have English as their milk tongue ;) but if you must use an idiom, at least use the right one. --Charlie — Preceding unsigned comment added by 205.153.180.229 (talk) 14:45, 21 February 2014 (UTC)

Cascading menus on the mac different

From the article: "where the user must travel from one end of the path to the other as quickly as possible, while staying within the confines of the path. One potential practical application of this law is in modelling a user's performance in navigating a hierarchical cascading menu."

On Macs, the previously pointed-at submenu is kept open even if the cursor travels over other items to remove the need of the user to stay "inside a corridor", therefore accelerating pointing operations. The algorithm checks whether the cursor trajectory actually moves towards the submenu at a certain minimum speed, which has been chosen pretty well (though some users feel that the OS9 speed was perfect and the OSX speed is set highter, too high actually, so the submenu closes for very slow mousers). Anyway, this could be added to the article, somehow. Cheers! Peter S. 23:04, 10 October 2005 (UTC)

This MacOS functionality can be described as a triangular corridor with associated minimum speed limit.

Original research: In Windows 7, at least in some applications, the submenu stays open even if you wander off the narrow path for a very brief time. I am not sure if this an implementation of a “triangular corridor” or a consequence of a delay time in closing the submenu. Solo Owl 08:35, 30 March 2015 (UTC)

Prior work, attribution, and name of the law

I feel that it is entirely inappropriate for the so-called steering law to be called Accot's law. Accot was about 26 years late in coming up with this law. many of us know it as Drury's law after its original developer Colin Drury of State University of New York Buffalo. Accot is aware that Drury was the first to come up with this law and i am sure that he must be embarrassed that it has been put in his name. 26 years and many publications is a travesty of justice in naming a law. The problem appears to be that people working in HCI do not read other journals that publish similar material

Errol Hoffmann, PO box 89 Halls Gap, Vic 3381 Australia

• Please don't type in all-uppercase (I've reformatted the above post); it impairs legibility and might be seen as shouting. Note I've removed the following text from the second paragraph; it needs citations and cleanup before it might be worth re-inserting:

(Actually first published in the journal Ergonomics by Colin Drury in 1971, 26 years prior to Accot acknowledging it -- to many it is known as Drury's law as he was certainly the discoverer of the law. To call it Accot's law is far from correct and the error must be corrected. Credit where it is due)

Irrel 17:25, 1 April 2007 (UTC)

I've added some references to earlier work by Drury and by Rashevsky. I haven't had time to look up and read the work by Drury or by Rashevsky, however it is discussed a bit in the Zhai, Accot, and Woltjer (2004) article. I trust that Prof. Errol Hoffmann has some valid concerns over calling the steering law "Accot's law", or the "Accot-Zhai" law, so perhaps a compromise would be to change the name of the article to "Steering law". However, from the discussion in Zhai, Accot, and Woltjer (2004), it's not clear to me how Drury's prior work was empirically verified. Was it verified with a driving task involving an automobile? Or with users holding a pointing device? Would it be fair to say that the task tested by Accot and Zhai, where the user steers with a pointing device and a bird's eye view of the tunnel, had never been tested before Accot and Zhai's work? Would it also be fair to say that the mathematical formulation given by Accot and Zhai is more general? If so, these things could be pointed out in a revised wikipedia article. Perhaps the Steering law in a general sense can be attributed to Rashevsky and/or Drury, however perhaps the demonstration of its validity in tasks with hand-held pointing devices and a bird's eye view of the tunnel is properly due to Accot and Zhai. MichaelMcGuffin 20:14, 2 April 2007 (UTC)

Response by Shumin Zhai

(BEGIN: note added by Shumin Zhai, 00:13, 6 April 2007 (UTC))

This is Shumin Zhai, one of the co-authors of (Accot & Zhai, 1997, 1999, 2001, 2002; and Zhai, Accot, & Woltjer, 2004).

I have not edited any entry of wikipedia. I thought it was particularly inappropriate for me to edit this entry on steering law since it involved our own work. However, given Dr. Hoffmann's recent comments I feel it should be helpful to share our knowledge in this discussion page.

We were not aware of Drury's work when we did our studies on path steering (Accot & Zhai, 1997, 1999, 2001), which is very unfortunate. In 2002, for a study on 2D Fitts' law effect (Accot & Zhai, 2003), we read (Hoffmann & Sheikh, 1994) which references (Drury, 1971). We were very surprised that we did not know about this related work earlier, considering that hundreds of people had read our papers or heard our talks on the law of steering, including many experts in motor control, manual tracking, driving research, and human factors and psychology in general but none of them knew about Drury’s work. Once I discussed the steering law at a party attended by many knowledgeable engineering psychologists and noted human factors pioneers, no one made the connection with Drury’ work while Prof. Drury himself was at the party. It is unfortunate that Drury’s important work was not better known. I found Drury and colleagues' later work (Drury, Montazer, & Karwan, 1987; Montazer, Drury, & Karwan, 1988) also very interesting but they too were largely unnoticed in the literature. To date, I cannot find any reference to (Drury, 1971) in major handbooks, textbooks, or surveys such as (Boff, Kaufman, & Thomas, 1986; Keele, 1986; Schmidt, 1988; Wickens, 1992; Helander, Landauer, & Prabhu, 1997). This is in a sharp contrast with Fitts' law on pointing, which has countless citations and descriptions.

In further research after discovering Drury's work, we also found that the basic thought that a regularity existed in steering was also put forward by Rashevsky in as early as 1959 (Rashevsky, 1959, 1965, 1970). Part of the problem was the different authors were motivated with different problems and used different words to describe a novel concept (at least novel to them). Suggested by a colleague of mine, we used the term steering to describe movement control within a constrained path. We cannot be sure that Rashevsky was necessarily the very first in dealing with a steering model.

We wrote a short review paper about the early literature and the differences among the three separate lines of studies. We submitted it to CHI 2003 but unfortunately it was rejected, on the ground that the steering law work was not relevant to HCI, probably due to the fact that driving was the primary concern in Rashevsky’s and Drury’s work. Part of the rejected paper was later incorporated in (Zhai, Accot, & Woltjer, 2004).

The findings in Accot and Zhai (1997) in parts rediscovered the early works by Rashevsky and Drury. There were also new findings including path steering with varying width, path steering with complex spiral shape, and the general form of steering law (the line integral of the inverse of the path width as the index of steering difficulty). Perhaps the most interesting aspect of Accot and Zhai (1997) was the "thought experiment" that connected the steering law with Fitts' law, using goal crossing as intermediate steps. That was probably why the original author of this entry, who succinctly summarized the main ideas in Accot and Zhai (1997) did not revise the entry when I first read the entry and informed him about Drury and other prior work. --- Shumin Zhai

References:

Accot, J. (2001). Les Tâches Trajectorielles en Interaction Homme-Machine — Cas des tâches de navigation. Unpublished Ph.D. Thesis, Université de Toulouse 1, Toulouse, France.

Accot, J., & Zhai, S. (1997). Beyond Fitts' law: models for trajectory-based HCI tasks. Proc. CHI 1997: ACM Conference on Human Factors in Computing Systems, 295-302.

Accot, J., & Zhai, S. (1999). Performance Evaluation of Input Devices in Trajectory-based Tasks: An Application of Steering Law. Proc. CHI 1999: ACM Conference on Human Factors in Computing Systems, 466-472.

Accot, J., & Zhai, S. (2001). Scale effects in steering law tasks. Proc. CHI 2001: ACM Conference on Human Factors in Computing Systems, CHI Letters 3(1), 1-8.

Accot, J., & Zhai, S. (2002). More than dotting the i's - foundations for crossing-based interfaces. Proc. CHI 2002: ACM Conference on Human Factors in Computing Systems, CHI Letters 4(1), 73 - 80.

Accot, J., & Zhai, S. (2003). Refining Fitts' law models for bivariate pointing. Proc. CHI 2003, ACM Conference on Human Factors in Computing Systems, CHI Letters 5(1), 193-200.

Boff, K., Kaufman, L., & Thomas, J. (1986). Handbook of perception and performance. New york: John Wiley & Sons.

Drury, C. G. (1971). Movements with lateral constraint. Ergonomics, 14(2), 293-305.

Drury, C. G., Montazer, M. A., & Karwan, M. H. (1987). Self-paced Path Control as an Optimization Task. IEEE Transactions on Systems, Man, And Cybernetics, 17(3), 455-464.

Helander, M., Landauer, T., & Prabhu, P. (1997). Handbook of Human-Computer Interaction (2nd ed.) Amsterdam: Elsevier.

Hoffmann, E. R., & Sheikh, I. H. (1994). Effect of varying target height in a Fitts' movement task. Ergonomics, 36(7), 1071-1088.

Keele, S. W. (1986). Motor Control. In K. R. Boff, L. Kaufman & J. P. Thomas (Eds.), Handbook of Perception and Human Performance (pp. 30.31-30.60). New York: John Wiley & Sons.

Montazer, M. A., Drury, C. G., & Karwan, M. H. (1988). An Optimization Model of Self-paced Tracking on Circular Courses. IEEE Transactions on Systems, Man, And Cybernetics, 18(6), 980-916.

Rashevsky, N. (1959). Mathematical biophysics of automobile driving. Bulletin of Mathematical Biophysics, 21, 375-385.

Rashevsky, N. (1965). Man-machine interaction in automobile driving. Traffic safty, 9, 161-167.

Rashevsky, N. (1970). Mathematical biology of automobile driving IV. Bulletin of Mathematical Biophysics, 32, 71-.

Schmidt, R. A. (1988). Motor control and learning - A Behavioral Emphasis ( 2nd ed.): Human Kinetics Publishers, Inc.

Wickens, C. D. (1992). Engineering Psychology and Human Performance: HarperCollines Publishers.

Zhai, S., Accot, J., & Woltjer, R. (2004). Human Action Laws in Electronic Virtual Worlds - an empirical study pf path steering performance in VR. Presence, 13(2), 113-127.

(END: note added by Shumin Zhai, 00:13, 6 April 2007 (UTC))

---

Oh, well, yet another example of Stigler's law – No scientific discovery is named after its original discoverer. Solo Owl 08:53, 30 March 2015 (UTC)

Steering through sharp curves

Anyone who has ever driven a car (or navigated through cascading submenus) knows that you have to slow down at a sharp curve. As presented here, the Steering Law ignores this complication. This a serious deficiency.

Have any of the discoverers, or other researchers, acknowledged this shortcoming? If so, Wikipedia should mention that. If anyone has attempted to modify the Steering Law to account for the amount of curvature, that should be mentioned also. Solo Owl 08:49, 30 March 2015 (UTC)