Fitts, P. M. (1954). A Web-based Test of Fitts' Law. Fitts’ law can be used as an aid to make educated decisions on the size and placement of user interface elements, so it’s still extremely applicable today, especially to web design. Fitts’ Law. A test of Fitts' law with moving targets Hum Factors. Front-End & UX Workshops, Online. doi:10.1145/142750.142794. It can, however, help in exploring different settings and be a usefull tool for constructing real Fitts's experiments. Figure 5 finally shows the movement speed in pixel per ms over the movement time.
This is not a controlled experiment, and no definitive truths should be derived from it. fig. It should also follow the ISO standard [ISO 9241-9] which unfortunately was unavailable to us at the time of writing. Traditionally, Fitts’ Law is formulated as: MT = a + b log 2 (2D /W), where a and b are empirical constants. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Each 'condition' was repeated 20 times in random order. The information capacity of the human motor system in controlling the amplitude of movement. ISO 92419. International Organization of Standardization. This Law states exactly how the time it takes is a function of the combination distance to the object and its size. Further reading The ID Test is written in Java by Barton Smith at the IBM Almaden Research Center, partially for … Odlanier2011. There is quite some room for improvement and we'd love to hear your feedback and comments. Soukoreff, R., & Mackenzie, I. In 1954, Fitts described the relationship between the target distance, width, and time needed for a target acquisition task. Fitts’ Law • Fitts’ Law or Fitts’s Law (never call it Fitt’s Law) • Named after Paul Fitts, for his 1954 study of pointing. There are no foreseeable risks in this study. Individual who is performing a skill will sacrifice speed for accuracy or vice versa has been termed the speed accuracy tradeoff. The Definition of Fitts Law in its simplest form. Someone NOT Like You
Key Concepts: Terms in this set (50) Fitts' Law specifies that performance will show a speed-accuracy trade-off in a rapid manual aiming task according to the relationship between which two characteristics of the task? 1d: Click position relative to approach direction. This is partly w… 5: Movement speed in px/ms over time in ms. If you are using a mobile device, please CLOSE THE KEYBOARD before you press start. By his law, fast movements and small targets result in greater error rates, due to the speed-accuracy trade-off. Group Members: Simon Wallner, Otilia Danet, Trine Eilersen, and Jesper Tved. All times are in milliseconds. Some of the major implications for user interface design and user experience in turn are considered below:1. It will start with 3 rounds of practice. Each test had two variables: the width of the ribbons and the space between the ribbons. doi:10.1016/j.ijhcs.2004.09.001, Bootsma, R. J., Fernandez, L., & Mottet, D. (2004). To test the hypothesis that Fitts’ Law can be applied to hand/air gesture based computing inputs, Fitts’ multi-directional target acquisition task is applied to three gesture based input devices that utilize different technologies and two baseline devices, mouse and touchscreen. Psychology Definition of FITTS LAW: a principle of motor control where activities done quicker can be less accurate than those activities done slower. Behind Fitts's law: kinematic patterns in goal-directed movements. Here are the results of your Fitts' law tests. In 1954, psychologist Paul Fitts, examining the human motor system, showed that the time required to move to a target depends on the distance to it, yet relates inversely to its size. Throughput is computed as IDe/movement time and therefore has the unit bits/second. This formula, known as Fitts’ Law, has been shown to hold across a wide range of tasks, including movements of the hand, hand-held tools (Fitts, 1954), or a mouse-controlled cursor (Radwin, Vanderheiden, & Lin, 1990). Fitts’ law is centered around a mathematical equation that is used to illustrate the time it takes to reach a target object. Fitts's Law is one of the cornerstones of user interface research. Fitts’ law is centered around a mathematical equation that is … Fitts' Law: The time to acquire a target is a function of the distance to and size of the target. Towards a standard for pointing device evaluation, perspectives on 27 years of Fitts's law research in HCI. Test of Pointing Speed and Accuracy Homework 1: Evaluate Pointing Devices & Fitts Law For 05-640: Interaction Techniques, Spring, 2019. Below you can see the test area. Optional extra participant
Fitts’ Law predicts that the time to point at an object using a device is a function of the distance from the target object & the object’s size. International Journal of Human-Computer Studies, 61(6), 811-821. doi:10.1016/j.ijhcs.2004.09.004. We are studying Fitts' Law, a model of human motor response developed by Paul Fitts in 1954. Fitts’s Law is about how long it takes to move your hand to an object. Fitts’ Law can draw many conclusions, however, the summary is quite simple: “The time to acquire a target is a function of the distance to and size of the target.” We developed on Safari and Chrome, so support for other modern browsers is likely but not guaranteed. Extending Fitts's law to two-dimensional tasks. This interactive experiment was created as part of an assignment for the User Interface Technologies course at the University of Copenhagen in spring 2012. fig. Width (centimeters):
Match. fig. This interactive illustration of Fitts's test should serve as an introduction to Fitts' law. Created by. Please be sure not to change the orientation of the device or resize the window. UC Berkeley Dataset of 94,580 human motion timing measurements. 1c: Movement speed in px/ms over time in ms. fig. Fitts's Law is one of the cornerstones of user interface research. Proceedings of the SIGCHI conference on Human factors in computing systems CHI 92, p, 219-226. The plots below show different evaluations of the test data. Evaluating input devices or methods for selecting targets on a computer display. By his law, fast movements and small targets result in greater error rates, due to the speed-accuracy trade-off. This test setup is merely for educative and illustrative purposes. For consistency, be sure to interact the same way throughout the test. Figure 2 shows a scatter plot of time over effective ID. Fitts's Law describes how long it takes a user to hit a target in a graphical user interface (GUI) or other design, as a function of size and distance. Authors R J Jagacinski, D W Repperger, S L Ward, M S Moran. A guide to increasing conversion and driving sales. It is a speed accuracy trade-off. Analysing the user's movements beyond Fitts's law can yield additional insights into different qualities of various input devices. To make an encompassing assessment further metrics have to be used (e.g. The Fitts tasks are considered to be spatially constrained, whereas the Schmidt tasks are temporally constrained. You're goal is to tap the blue ribbons as QUICKLY and as ACCURATELY as possible. These plots update automatically after an inactivity of 2 seconds. Fitts's Law describes how long it takes a user to hit a target in a graphical user interface (GUI) or other design, as a function of size and distance. A Web-based Test of Fitts' Law. 1. (cp) Interface Design Checklists (PDF) 100 practical cards for common interface design challenges. Throughput and its distribution can be one of the indicators of a device's performance. For measuring, Fitts' law provides a method to quantify human performance in a single measure, "throughput". Someone Like You
Fitts law would provide the Interface designers a way of dealing with the usability and user experience dimensions in a quantifiable measure using the mathematical equations. to compare different input devices or parameters) and the test parameters (distance and width) can be adjusted. According to Fitts' law, human movement can be modeled by analogy to the transmission of information. Not long after the original model was proposed, a 2-factor variation was proposed under the intuition that target distance and width have separate effects on movement time. It can also help the reader to visualise details not directly covered by the law and give further insights into motion in 2D target acquisition tasks. 1a: Test Area: Try to click the red circle as fast as possible but at the same time try to avoid errors. The bigger an object and the closer it is to us, the easier it is to move to. PLAY. fig. The effective Index of Difficulty (IDe) is computed as follows: fig. Click! The test is laid out according to the recommendations found in [Soukoreff and Mackenzie 2004]. Although the mechanisms that produce Fitts’ Law are still under debate, the Law is likely to reflect processes at the level of motor planning (Gutman and Latash, 1993; Duarte and Latash, 2007; Bertucco and Cesari, 2010). (2000). In the case of the Jeep Cherokee, the increased distance combined with a break in convention made it difficult for people to step on the brake when they wanted to. Fitts Law Fitts law is a descriptive model of human movement. The user needs much less precision because they can simply fling the mouse in the direction of a corner and the limitations of the screen restrict where the pointer ends up. (2004). Command buttons and any other interactive element in the graphical user interface must be distinguished from other non-interactive elements by size. This project is licensed under the permissive MIT license, The full source is available on GitHub. Usually, though, it is merely a leading indicator of overall ignorance, amplified by superstition and unsullied by facts or study. 1980 Apr;22(2):225-33. doi: 10.1177/001872088002200211. In 1954, psychologist Paul Fitts, examining the human motor system, showed that the time required to move to a target depends on the distance to it, yet relates inversely to its size. Individual histograms for each data set are scaled to their respective maximum frequency. The objective of this study is to gather data about the speed with which humans move to targets of different sizes and at different distances. Below is a CSV-encoded copy of your results. Ergonomic requirements for office work with visual display terminals (VDTs) - Requirements for non-keyboard input devices. International Journal of Human-Computer Studies, 61(6), 751-789. Gravity. This later became known as Fitts's law [Fitts 1954]. There are two prominent speed accuracy tradeoff relationships; Fitts’ Law and Schmidt’s Law. Height (centimeters): Press the button to begin the test. Test. In 1954, Fitts described the relationship between the target distance, width, and time needed for a target acquisition task. Data is accumulated in the live plots as long as the test parameters remain unchanged. For instance, 0.5cm_X_2cm would mean that the ribbons were 0.5cm wide, and 2cm apart. Device (i.e. How Fitts’ Law Works. This interactive illustration of Fitts's test should serve as an introduction to Fitts' law. 2: Time in ms over effective ID. fig. Testing Fitts' law or building Fitts' law models. Welford's model, proposed in 1968, separated the influence of target distance and width into separate terms, and provided improved predictive power: In Figure 4 All data is anchored in the start position of each trial. Fitts' Index of Difficulty was found to be a good predictor of capture time for the rate syste... A Test of Fitts' Law with Moving Targets - Richard J. Jagacinski, Daniel W. Repperger, Sharon L. Ward, Martin S. Moran, 1980 Distance to move and target size. For the sake of completeness and contrast we would like to refer to [Bootsma et al.
The size of a target and its distance from the user’s current position within the user interface affect user experience in a number of ways. Previous studies have allowed for the hypothesis that these two laws may be related … The personal information to be collected in the study will not be linkable to individual participants in the study. fig. A Quiz Designed to Give You Fitts A small quiz to test your knowledge of Fitts’s Law.
touchpad, mouse...): Please measure the width and height of your screen using a ruler so we can accurately scale the test. Each test had two variables: the width of the ribbons and the space between the ribbons. You can select the text and then paste it into a text file or email. The test setup allows for multiple data sets to be created (e.g. Three target distances and three target sizes For predicting, Fitts' law is an equation giving the time to acquire and select a target based on the distance moved and the size of the target. Draft Paper: A New Derivation and Dataset for Fitts' Law of Human Motion. Figure 3 shows a histogram of the throughput for each dataset. error rate, and overall user comfort and user satisfaction). ACM Press. You can address them to Simon via email. Fiits’ law states that the time required to move to a target is a function of the target size and distance to the target.. From this formula we can see that the task gets harder, the farther away the target is and the smaller it is. Based on your results, discuss pros and cons of the pointing devices: suggest improvements or new designs. ISO. His original study was on pointing with a stylus, but his work is applicable to pointing with a mouse, using touch screens, and the range of pointing devices for 2D displays. Participant Type:
This later became known as Fitts's law [Fitts 1954]. 2004]. For a given target acquisition task, e.g. If parameters are set randomly, they will update after each test round, to allow for the continuous insertion of test data for different conditions. Beneath it you can find various plots that update in real time while data is entered. Begin Test. All times are in milliseconds. 3: Histogram of effective throughput. Yourself
Fitts' popular model has been widely adopted in numerous research areas, including kinematics, human factors, and (recently) human-computer interaction (HCI). As it turns out, the time it takes to perform such a task is linearly correlated with its ID. Discuss the benefits of Fitts' Law. Journal of Experimental Psychology, 47(6), 381-391. doi:10.1037/h0055392, MacKenzie, I. S., & Buxton, W. (1992). If you save the text in a file called 'results.csv', then you can load it up in Excel, Google Docs, or other spreadsheet programs. This little bit of obviousness is so often ignored, I sometimes wonder if it is on purpose. The law (in the Shannon formulation [MacKenzie and Buxton 1992]) states that. A Web-based Test of Fitts' Law.
1b: Deviation form straight path over path distance in px. move the mouse to a certain point in the UI of an application and select it, Fitts's law desribes how the distance from start point to the target and the width of the target influence the index of difficulty (ID) of the task. Below you can find an interactive Fitts's test. These two figures illustrate the mouse's movement path and speed during the test.