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Cited by 337Interactive and Immersive DisplaysUsability and User Interface DesignInnovative Human-Technology Interaction

A morphological analysis of the design space of input devices

Open access
Card, Stuart K., Mackinlay, Jock D., Robertson, George G.·1991·ACM Transactions on Information Systems
DOI 10.1145/123078.128726
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Abstract

The market now contains a bewildering variety of input devices for communication from humans to computers. This paper discusses a means to systematize these devices through morphological design space analysis, in which different input device designs are taken as points in a parametrically described design space. The design space is characterized by finding methods to generate and test design points. In a previous paper, we discussed a method for generating the space of input device designs using primitive and compositional movement operators. This allowed us to propose a taxonomy of input devices. In this paper, we summarize the generation method and explore the use of device footprint and Fitts's law as a test. We then use calculations to reason about the design space. Calculations are used to show why the mouse is a more effective device than the headmouse and where in the design space there is likely to be a more effective device than the mouse.

Integrity signals

Registry

Crossref · 10.1145/123078.128726

Cites

43 of 43 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 15 cited sources checked · 0 supported · 0 flagged

  • Findingnone given

    The manipulation operators in Table I represent all combinations of linear and rotary, absolute and relative, and position and force.

    “They represent all combinations of linear and rotary, absolute and relative, and position and force.”
    Quote in the paperSubstantial claim
  • Findingcitation

    The model of the input device design space has been used to help design novel egocentric motion devices for virtual 3-D environments.

    “In particular, we have used our model of the input device design space to help design novel egocentric motion devices for virtual 3-D environments [23,29].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [23] 23. MACKINLAY, J. Automatic design of graphical presentations. Ph.D. dissertation Computer Science Dept., Stanford Univ., Calif., 1986. (Also Tech. Rep. Stan-CS-86-1038. source
    • cites [29] 29. PFAFF, G. E.. User Interface Management Systems. Springer-Verlag, New York, 1985. source
  • Findingown data

    With the exception of voice, all of the devices considered so far can be positioned in the taxonomy.

    “With the exception of voice, we have been able to position all of the devices considered so far.”
    Quote in the paperSubstantial claim
  • Findingown data

    The target size ranges from 5.5 cm for a typical paragraph to 0.069 cm for a period.

    “The target size (column (1) in the table) ranges from 5.5 cm for a typical paragraph to 0.069 cm for a period.”
    Quote in the paperNot a substantial claim
  • Findingown data

    The tablet and the mouse are very expensive in footprint relative to other devices.

    “Several facts about the design space of potential devices are evident from the diagram: (1) The tablet and the mouse are very expensive in footprint relative to other devices.”
    Quote in the paperNot a substantial claim
  • May combine two claims. 14
  • Classified as probably not a substantial claim. 24
  • The quote only partly states this claim. 1

  • May combine two claims.

    Findingnone given

    Two devices (trackball and joystick) have small footprints that are independent of screen size.

    “Two of the devices (trackball and joystick) have small footprints that are independent of screen size.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingreasoning

    The lines in Figure 7 have intercepts near, but not exactly at, the origin.

    “The lines in Figure 7 have intercepts near, but not exactly at, the origin.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingreasoning

    The computed precision of the headmouse is 2.0 bits, compared to 4.6 bits for the mouse.

    “Using eq. ( 2), the precision of the headmouse is 440 ms/(240 ins/bit) = 2.0 bits, as compared to the 4.6 bits we computed for the mouse earlier”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The typical target distance is 9.7 cm, half way from the center of a 19-inch screen to the side edge.

  • May combine two claims.

    Findingnone given

    Three devices (light pen, on-screen touch pad, and rotary potentiometers) require no additional footprint.

    “Three of the devices (light pen, on-screen touch pad, and rotary potentiometers) require no additional footprint (assuming that no footprint is needed to store the lightpen and that the potentiometers mount on the case).”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: No footprint is needed to store the lightpen and the potentiometers mount on the case.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). The quote only partly states this claim.

    Findingreasoning

    Pointing to a word at the assumed distance of 9.7 cm with a mouse bandwidth of 96 ins/bit takes about 220 ms.

    “= 96 ins/bit”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: The typical target distance is 9.7 cm, half way from the center of a 19-inch screen to the side edge.

  • Probably not a substantial claim: may not pass S4 (based).

    Findingnone given

    Pointing to a character at the assumed distance takes 440 ms.

    “Pointing to a character at our assumed distance takes 440 ms.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: The typical target distance is 9.7 cm, half way from the center of a 19-inch screen to the side edge.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingreasoning

    The intercepts vary slightly from line to line and make comparisons among the muscle groups more difficult.

    “These vary slightly from line to line and make comparisons among the muscle groups more difficult.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingreasoning

    The computed device precision for the fingers is 17.6 bits, almost four times as much as for the mouse.

    “The computed device precision for the fingers is 17.6 bits, almost four times as much as for the mouse.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The typical target distance is 9.7 cm, half way from the center of a 19-inch screen to the side edge.

  • May combine two claims.

    Premisecitation

    Card, English, and Burr [9] confirmed that the mouse is the fastest device and discovered that pointing speed with the mouse is governed by Fitts's law with a bandwidth similar to that of the hand.

    “Card, English, and Burr [9] confirmed these empirical results and discovered that pointing speed with the mouse is governed by Fitts's law [14] with a bandwidth similar to that of the hand.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [9] 9. CARD, S. K. Human factors and artificial intelligence, In Intelligent Interfaces; Z%eory, Research and Design, P. A. Hancock and M. H. Chignell, Eds. Elsevier Science Publishers B. V., North-Holland, Amsterdam, 1989, pp. 270-284. source
    • cites [14] 14. EPPS, B., SNYDER, H., AND MUTOL, W. Comparison of six cursor devices on a target acquisition task. In Proceedings of the Society for Information Display (San Diego, Calif., May 6-8, 1986). Society for Information Display, 1986, pp. 302-305. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    English and Engelbart [12] found the mouse the fastest device among several devices studied.

    “English and Engelbart [12] studied several devices and found the mouse the fastest device.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [12] 12. CASNER, S. M. A task-analytic approach to the automated design of graphic presentations. ACM Trans. Graph. 10, 2 (Apr. 1991), 111-151. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    Performance studies have not always agreed, largely because some studies have not attempted to disentangle task, subject, and human performance variables.

    “Unfortunately, these studies have not always agreed, largely because some studies have not attempted to disentangle task, subject, and human performance variables.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Virtually all input devices use some combination of the properties listed in Table I.

    “Although other input devices are possible (based, say, on speech or heat), virtually all input devices use some combination of the properties listed in Table I.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisenone given

    There are three composition operators: merge composition, layout composition, and connect composition.

    “There are three composition operators: (1) merge composition, (2) layout composition, and (3) connect composition.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    The actual footprint of some devices such as the mouse depends on the sequence of actions in an application.

    “The actual footprint of some devices such as the mouse depends on the sequence of actions in an application.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    Figure 3 is a sufficiently rich depiction of the design space for input devices that it can be used both to classify nearly all existing devices and to generate ideas for new devices not yet invented.

    “the point is that Figure 3 is a sufficiently rich depiction of the design space for input devices that it can be used both to classify nearly all existing devices and to generate ideas for new devices not yet invented.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    The speed and error performance of a particular device may depend on subtleties such as the relationship between the geometry of the device and the geometry of the hand or coefficients of friction.

    “The speed and error performance of a particular device may depend on a number of subtleties such as the relationship between the geometry of the device and the geometry of the hand or coefficients of friction.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    In the virtual head movement application, the headmouse is precise enough for the viewing task but not precise enough for the pointing task.

    “According to the figure, the headmouse, with precision slightly larger than a word, is precise enough for viewing but not for pointing.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: Moving the virtual head to look around in the virtual 3-D world is roughly equivalent in difficulty to pointing to a paragraph, and pointing to objects is roughly equivalent to pointing to a character.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    The device itself can degrade the achievable performance.

    “Of course, the device itself can degrade the achievable performance.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    The mouse is more precise than the headmouse; the headmouse could only point to a target with an Index of Difficulty 39 percent as great in the same amount of time.

    “This means that the mouse is more precise.To be concrete, it means that the headmouse could only point to a target with an Z~= 1.8/4.6 = 39 percent as great in the same amount of time.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The typical target distance is 9.7 cm, half way from the center of a 19-inch screen to the side edge.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisereasoning

    Devices in the modeling scheme do not have to be physical devices, but can also be virtual devices implemented in software, such as the cursor.

    “This illustrates another point about the modeling scheme, namely, that devices do not have to be physical devices, but can also be virtual devices implemented in software, such as the cursor.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    If the projection of the Out set includes elements that are not in the In set, the user can specify illegal values; if the In set includes values that are not in the projection, the user cannot specify legal values.

    “If the projection of the Out set includes elements that are not in the In set, the user can specify illegal values; and if the In set includes values that are not in the projection, the user cannot specify legal values.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    These figures of merit include human performance measures such as speed and errors, as well as pragmatic concerns such as desktop footprint, panel space, or cost.

    “These figures of merit include human performance measures such as speed and errors, as well as pragmatic concerns such as desktop footprint, panel space, or cost.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Different muscle groups give rise to different Fitts's law slopes.

    “Langolf observed the approximate muscle groups being used and made the observation that different muscle groups gave rise to different Fitts's law slopes.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [18] 18. S. K. Card, et al. 17, 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32 33, 34. 35. 36

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    The comparisons made in the paper are not very sensitive to the exact values selected for the parameters.

    “Nonetheless, the comparisons we shall make are not very sensitive to the exact values selected for the parameters.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: The typical target distance is 9.7 cm, half way from the center of a 19-inch screen to the side edge.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    Variants in devices (e.g., in input or output domains or mappings) are possible below the level of detail visualized in Figure 3.

    “It is important to note that each group of linked circles in Figure 3, which collectively represent a device, is only a single point in a very large design space and that variants in devices are possible (e.g., in the input or output domains or the mappings), which are below the level of detail visualized in the figure.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    In some design spaces, expressiveness is a major concern.

    “In some design spaces, expressiveness is a major concern.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    In the design of input devices, an expressiveness problem arises when the number of elements in the Out set does not match the number of elements in the In set to which it is connected.

    “In the design of input devices, an expressiveness problem arises when the number of elements in the Out set does not match the number of elements in the In set to which it is connected.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    Using a headmouse instead of a mouse shifts the spectrum of pointing times to the right, so easy tasks become hard or moderate.

    “The spectrum of pointing times is shifted to the right.Easy tasks become hard or moderate.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The typical target distance is 9.7 cm, half way from the center of a 19-inch screen to the side edge.

  • May combine two claims.

    Interpretationown data

    In the virtual head movement application, the mouse is precise enough for both the viewing and pointing tasks.

    “Since the task circles contain the filled circles projected from the mouse, it is clear that the mouse is precise enough for both tasks.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: Moving the virtual head to look around in the virtual 3-D world is roughly equivalent in difficulty to pointing to a paragraph, and pointing to objects is roughly equivalent to pointing to a character.

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    The combination of primitive moves and composition operators gives a parametric abstract representation that represents the space of sentences it is possible to transmit.

    “The combination of primitive moves and composition operators gives us a parametric abstract representation that represents the space of sentences it is possible to transmit.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given

    The design space for input devices is basically the set of possible combinations of the composition operators with the primitive vocabulary.

    “The design space for input devices is basically the set of possible combinations of the composition operators with the primitive vocabulary.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationnone given

    The three buttons of a mouse and the XY sensors are all four layout-composed together to form the mouse.

    “The three buttons of a mouse and the XY sensors are all four layout-composed together to form the mouse.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    For the mouse, the output is connected to the input for the screen cursor.

    “For the mouse, the output is connected to the input for the screen cursor.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    The muscle group to which an input device is connected determines an upper bound on the device's bandwidth, as indexed by the Fitts's law slope.

    “This determines an upper bound on the bandwidth of the device (as indexed by the Fitts's law slope).”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    This generates the design space of input devices.

    “In a sense, this generates the design space of input devices.”
    Quote in the paperSubstantial claim
35 of 35

  • The authors state this as an assumption.

    Functions of the application program express the semantics of the interaction.

    “In our analysis, we make the idealized assumption that functions of the application program express the semantics of the interaction.”

  • The authors state this as an assumption.

    Input devices can be treated as idealized devices without stickiness, significant lags, noise, or linearity problems.

    “Generally, we assume somewhat idealized devices without stickiness, significant lags, noise, linearity problems, etc.”

  • The authors state this as an assumption.

    It is possible to express the user's intention in a sentence in the repertoire of the input device.

    “Assuming that it is possible to express the user's intention in a sentence in the repertoire of the input device, there is still the question of how well this can be done in terms of speed, errors, or other figures of merit for an input device (in a particular task for a particular user).”

  • The authors state this as an assumption.

    No footprint is needed to store the lightpen and the potentiometers mount on the case.

    “assuming that no footprint is needed to store the lightpen and that the potentiometers mount on the case”

  • The authors state this as an assumption.

    The typical target distance is 9.7 cm, half way from the center of a 19-inch screen to the side edge.

    “Since we do not have specific data on target distance, the calculation assumes a typical distance of half way from the center of a 19”

  • The authors state this as an assumption.

    The performance of many devices is more or less set by the muscle groups with which the device is designed to connect.

    “For the moment, we assume that this is so in order to compute the inherent limitations imposed on a device by the muscle group to which it is connected.”

  • The authors state this as an assumption.

    Moving the virtual head to look around in the virtual 3-D world is roughly equivalent in difficulty to pointing to a paragraph, and pointing to objects is roughly equivalent to pointing to a character.

    “For purposes of the calculation, we have assumed that moving the virtual head to look around in the virtual 3-D world is roughly equivalent in difficulty to pointing to a paragraph, and that pointing to objects is roughly equivalent to pointing to a character, which is also the easiest hard task for the mouse.”
7 of 7

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Headmouse precision calculation gives 1.8 bits, not 2.0

    Minor

    Dividing 440 ms by 240 ms/bit gives about 1.83 bits. The reported 2.0 bits also disagrees with the 1.8 bits listed for the headmouse in Table IV.

    Reported 2 · recomputed 1.833333

  • Precision formula names the wrong task boundary

    Minor

    The paper identifies a word as the hardest easy target and gives it a pointing time of 220 ms. The precision formula instead labels 440 ms-the time assigned to the easiest hard target-as the time for the hardest easy task.

2 of 2

Cites

Flagged first, then by citations

Research works printed but not linked: 16

  1. APPLE COMPUTER, 1987, Mass.
  2. BERTZN J., 1973, Wis., 1983
  3. BLESER T. W., 1990, Proceedings of User Interface Software and Technology, 135
  4. EPPS B., 1986, Proceedings of the Society for Information Display
  5. JELL~EK H., 1990, CHI'90 Conference Proceedings, 213
  6. KARAT J., 1985, Ed. Elsevier North-Holland, 189
  7. LANOOLF G.D., 1973, Mich., 1973
  8. MACKENZ, 1991, Univ. of Toronto
  9. MACKINLAY J., 1986, Calif.
  10. OLSEN D. R., 1987, ET AL. ACM SIGGRAPH workshop on software tools for user interface management. Comput. Graph. 21, 71
  11. PENF LD, W, 1990, Macmfilan
  12. PFAFF G.E., 1985, Springer-Verlag
  13. ROTH S. F., Eds. ACM Press, 207
  14. SmWIOREK D. BELL G. AND NEWELL A. Computer Structures. McGraw-Hill New York 1981. SmWIOREK D. BELL G. AND NEWELL A. Computer Structures. McGraw-Hill New York 1981.
  15. TANNER P. P., 1985, Ed. Springer-Verlag, 67
  16. WELFORD A.T., 1968, Methuen

Cited by

Sorted by citations

Related

Authors
Card, S. K., Mackinlay, J. D., & Robertson, G. G.
Affiliations
Palo Alto Research Center (US)
Venue
ACM Transactions on Information Systems
Publisher
Association for Computing Machinery (ACM)
Published
1991-04
Volume
9
Issue
2
Pages
99-122
ISSN
  • 1046-8188 (ISSN-L)
  • 1558-2868
DOI
10.1145/123078.128726
OpenAlex
W2036024905
Semantic Scholar
01f4112e9ce1cca76c152ffd8836fcb18f7cfc63
Cited by
337
References
42
Citations by year
2026: 13 · 2025: 64 · 2024: 10 · 2023: 8 · 2022: 6 · 2021: 10 · 2020: 7 · 2019: 12 · 2018: 6 · 2017: 9 · 2016: 8 · 2015: 8 · 2014: 10 · 2013: 14 · 2012: 6
FWCI
3.26
Type
journal article
Language
en
Open access
Licence
www.acm.org/publications/policies/copyright_policy#Background (vor)
Locations
ACM Transactions on Information Systems (publishedVersion)
Topics
  • Physical Sciences › Computer Science › Human-Computer Interaction › Interactive and Immersive Displays
  • Physical Sciences › Computer Science › Human-Computer Interaction › Usability and User Interface Design
  • Physical Sciences › Computer Science › Human-Computer Interaction › Innovative Human-Technology Interaction
Keywords
input devices, design space analysis, human-computer interaction, device footprint, Fitts' law, mice, input device design

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