What is speed-accuracy trade off? This is the tendency when doing a task to go for speed or accuracy. One is sacrificed to support the other. Meaning in a speed-accuracy trade off, a low speed means higher accuracy and a higher speed means a decrease in accuracy. We all have experienced this trade-off in some instance. Maybe it was in sports activities or something as simple as moving your mouse. Meaning, that the faster you move your mouse the harder it is to click on an icon!!!
A way one can test the speed-accuracy trade off is Fitts Tapping Test. The goal of the tapping test is to minimize the number of target misses. In other words, we try and adjust movement time so that the errors are acceptably small [MT=A+B(ID)]. When the target size is increased, the accuracy requirements are relaxed and MT’s are smaller than when narrow targets are used. So in simple terms, when the target gets smaller or the distance gets farther we sacrifice time in order to be as accurate as we can. When the target gets bigger or the distance gets smaller we do not have to sacrifice as much time because the task becomes easier. Simply, less accuracy, less distance = and increase in speed accuracy tradeoff.
In doing this test what was my assessment of the differing ratio? It is as follows, when the amplitude and width stayed constant so did the MT. So very long movements to wide targets require about the same time as very short movements to narrow targets. MT is increased as the ratio of amplitude to width increased by making amplitude larger or making width smaller, or both. This leads me right into my next observation. Was this open or closed loop? Fitt’s Law describes the effectiveness of the combined open and closed-loop processes that operate in these common kinds of actions, where all the open and closed-loop processes show are operating together. What this means that it is a combination of open and closed-loop. There are rapid alterations between open and closed-loop processing. The open-loop is the initiation of movement toward the target and the closed-loop is the feedback phase correcting errors in the initial movement. It was closed as a whole 60 tap test and open for each tap loop.
Is the speed-accuracy trade-off true in all aspects? No, this leads us into the paradox. Sometimes, moving faster can make you more accurate. The general rule is that we trade speed for accuracy (or vice versa) when we make aiming movements. However, there are some exceptions. Research suggests that in some instances that faster might be better if the action requires us to move rapidly in the first place. Some examples of this could be throwing a pitch. If you try and slow things down to much it could cause you to be less accurate. The same thing as spiking a volleyball or swinging an axe. One still does not want to be out of control that will still cause you to be inaccurate. It means that one might improve their accuracy if they work to gradually increase the speed. If we gradually increase the speed of our wind-up when throwing a pitch, gradually increase our run, jump, and swing when spiking a volleyball, and gradually increasing the speed of the axe when chopping wood we can be more accurate.
References:
Great article. It makes sense just by reading but when put into practice, one is able to see instantly how speed will alter accuracy. No matter how goos someone can get at a skill or task, in order to increase the accuracy, they must slow down a bit. This can be applied to almost everything if not all.
ReplyDelete