APPENDIX B

This appendix contains summary data and scatter plots with regression lines for Experiment 1 for each device-task condition. Tables are based on adjusted data (see p. 82).

Legend
A Target amplitude (experimental units; 1 unit = 8 pixels).
W Target width (as above).
We(SD) Effective target width. Values were calculated using the standard deviation method. Each value is 4.133 times the mean of the 12 subject standard deviations in x coordinates
We(DE) Effective target width. Values were calculated using the discrete errors method. Each value is obtained using the method described on page 19 applied to the mean of the 12 subject values.
ID Index of difficulty (bits). Values were computed using Fitts' formulation, ID = log2(2A / W).
MT Movement time (ms). Each value is the mean of 12 subject means.
Errors Percentage errors. Each value is the mean of 12 subject means
IP Index of performance (bits/s). Each value is the mean of 12 subject means. (IP = ID / MT, as defined above).
TRIALS Number of trials used in the calculations. The maximum number for each entry was 600; however, cases were omitted for the first session (reducing the potential to 480 cases), outliers, and trials following outliers.

Condition: Mouse-Pointing

  A    W  We(SD)  We(DE)   ID    MT   Errors   IP  Trials
---------------------------------------------------------
  8    8   4.232   5.370   1    221    .21   4.72   474
  8    4   3.055   3.388   2    331   1.47   6.26   472
 16    8   5.691   6.266   2    303    .83   6.85   477
  8    2   1.738   1.817   3    488   2.29   6.35   478
 16    4   3.208   3.309   3    450   1.25   6.84   476
 32    8   6.235   6.462   3    445   1.05   6.83   476
  8    1   1.004   1.110   4    663   6.27   6.15   474
 16    2   1.839   1.871   4    620   2.72   6.54   478
 32    4   3.134   3.138   4    616    .84   6.54   474
 64    8   6.754   7.036   4    685   1.88   5.89   476
 16    1   1.034   1.065   5    802   5.24   6.33   478
 32    2   1.721   1.880   5    764   2.79   6.60   473
 64    4   3.535   3.707   5    868   2.58   5.80   472
 32    1   1.076   1.130   6    950   6.74   6.47   473
 64    2   1.852   1.937   6   1061   3.29   5.73   469
 64    1   1.041   1.075   7   1252   5.47   5.69   477
                               ------------------
                       Mean     657   2.81   6.22
                         SD     285   2.06    .56
Condition:       Mouse-Pointing                     MT = -33 + 172 ID
Formulation:     Fitts                              r = .9866
Target Width:    W                                  SE = 48.1 ms

Condition:       Mouse-Pointing                     MT = -179 + 198 ID
Formulation:     Fitts                              r = .9887
Target Width:    We(SD)                             SE = 44.4 ms

Condition:       Mouse-Pointing                     MT = -1.9 + 202 ID
Formulation:     Shannon                            r = .9920
Target Width:    W                                  SE = 37.4 ms

Condition:       Mouse-Pointing                     MT = -107 + 223 ID
Formulation:     Shannon                            r = .9902
Target Width:    We(SD)                             SE = 41.5 ms



Condition: Mouse-Dragging

  A    W  We(SD)  We(DE)   ID    MT   Errors   IP  Trials
---------------------------------------------------------
  8    8   6.024   7.267   1    438   2.29   2.33   476
  8    4   3.970   4.382   2    576   5.93   3.57   473
 16    8   6.972   8.054   2    556   4.01   3.66   475
  8    2   2.247   2.510   3    704   9.97   4.38   462
 16    4   3.625   3.980   3    673   3.78   4.54   474
 32    8   7.404   8.462   3    721   5.08   4.22   474
  8    1   1.436   1.428   4    878  14.79   4.68   468
 16    2   2.638   2.731   4    829  13.02   4.90   476
 32    4   4.138   4.715   4    866   7.96   4.66   472
 64    8   7.289   8.434   4    971   5.00   4.17   472
 16    1   1.459   1.537   5   1034  17.89   4.93   472
 32    2   2.574   2.714   5   1029  12.79   4.93   472
 64    4   4.766   4.382   5   1087   5.93   4.66   471
 32    1   1.512   1.460   6   1218  15.70   5.04   470
 64    2   2.529   2.757   6   1302  13.39   4.67   470
 64    1   1.641   1.574   7   1514  18.93   4.71   470
                               ------------------
                       Mean     899   9.78   4.38
                         SD     292   5.45    .69
Condition:       Mouse-Dragging                     MT = 195 + 176 ID
Formulation:     Fitts                              r = .9862
Target Width:    W                                  SE = 50.0 ms

Condition:       Mouse-Dragging                     MT = 92 + 212 ID
Formulation:     Fitts                              r = .9875
Target Width:    We(SD)                             SE = 47.6 ms

Condition:       Mouse-Dragging                     MT = 226 + 207 ID
Formulation:     Shannon                            r = .9914
Target Width:    W                                  SE = 39.5 ms

Condition:       Mouse-Dragging                     MT = 135 + 249 ID
Formulation:     Shannon                            r = .9921
Target Width:    We(SD)                             SE = 37.9 ms



Condition: Tablet-Pointing

  A    W  We(SD)  We(DE)   ID    MT   Errors   IP  Trials
---------------------------------------------------------
  8    8   4.034    .      1    254    .00   4.28   474
  8    4   2.845   3.517   2    353   1.88   6.12   480
 16    8   4.690   6.266   2    344    .83   6.40   476
  8    2   1.560   1.726   3    481   1.67   6.37   478
 16    4   3.231   3.577   3    472   2.08   6.55   477
 32    8   5.562   6.046   3    501    .63   6.24   470
  8    1   1.149   1.213   4    649   8.84   6.34   474
 16    2   1.629   1.796   4    603   2.14   6.77   470
 32    4   3.252   3.739   4    605   2.71   6.70   478
 64    8   6.624   7.381   4    694   2.51   5.88   474
 16    1   1.053   1.141   5    778   7.01   6.59   473
 32    2   1.795   1.952   5    763   3.42   6.62   470
 64    4   3.464   3.645   5    804   2.34   6.32   470
 32    1   1.165   1.200   6    921   8.50   6.63   472
 64    2   1.867   1.942   6    963   3.33   6.33   477
 64    1   1.301   1.252   7   1137   9.88   6.27   476
                               ------------------
                       Mean     645   3.61   6.28
                         SD     243   3.13    .58
Condition:       Tablet-Pointing                    MT = 53 + 148 ID
Formulation:     Fitts                              r = .9921
Target Width:    W                                  SE = 31.5 ms

Condition:       Tablet-Pointing                    MT = -124 + 181 ID
Formulation:     Fitts                              r = .9869
Target Width:    We(SD)                             SE = 40.7 ms

Condition:       Tablet-Pointing                    MT = 81 + 173 ID
Formulation:     Shannon                            r = .9951
Target Width:    W                                  SE = 25.0 ms

Condition:       Tablet-Pointing                    MT = -55 + 204 ID
Formulation:     Shannon                            r = .9876
Target Width:    We(SD)                             SE = 39.6 ms



Condition: Tablet-Dragging

  A    W  We(SD)  We(DE)   ID    MT   Errors   IP  Trials
---------------------------------------------------------
  8    8   5.078   6.912   1    365   1.68   2.92   472
  8    4   3.602   4.306   2    442   5.49   4.70   472
 16    8   6.061   6.471   2    493   1.06   4.27   472
  8    2   2.469   2.652   3    566  11.92   5.46   476
 16    4   3.650   4.308   3    595   5.51   5.17   468
 32    8   7.444   8.605   3    630   5.47   4.90   476
  8    1   1.536   1.616   4    761  20.11   5.47   476
 16    2   2.762   3.022   4    711  17.15   5.82   469
 32    4   4.979   4.915   4    735   9.26   5.54   470
 64    8   8.360   8.774   4    838   5.95   4.88   468
 16    1   1.675   1.767   5    937  24.21   5.47   470
 32    2   3.063   2.889   5    896  15.26   5.69   464
 64    4   4.762   5.051   5    973  10.17   5.27   465
 32    1   2.036   1.695   6   1112  22.27   5.58   462
 64    2   4.049   3.188   6   1132  19.48   5.44   464
 64    1   1.934   1.647   7   1397  20.96   5.18   465
                               ------------------
                       Mean     786  12.25   5.11
                          SD    280   7.72    .71
Condition:       Tablet-Dragging                    MT = 113 + 168 ID
Formulation:     Fitts                              r = .9830
Target Width:    W                                  SE = 53.2 ms

Condition:       Tablet-Dragging                    MT = -80 + 235 ID
Formulation:     Fitts                              r = .9886
Target Width:    We(SD)                             SE = 43.7 ms

Condition:       Tablet-Dragging                    MT = 142 + 198 ID
Formulation:     Shannon                            r = .9905
Target Width:    W                                  SE = 40.0 ms

Condition:       Tablet-Dragging                    MT = -27 + 276 ID
Formulation:     Shannon                            r = .9925
Target Width:    We(SD)                             SE = 35.4 ms



Condition: Trackball-Pointing

  A    W  We(SD)  We(DE)   ID    MT   Errors   IP  Trials
---------------------------------------------------------
  8    8   5.503   5.370   1    485    .21   2.17   480
  8    4   3.177   3.384   2    613   1.46   3.43   480
 16    8   5.958   6.266   2    613    .83   3.45   480
  8    2   1.778   1.818   3    819   2.30   3.87   478
 16    4   3.357   3.313   3    766   1.26   4.15   474
 32    8   6.699   6.453   3    887   1.04   3.45   480
  8    1   1.189   1.208   4   1094   8.71   3.73   468
 16    2   1.765   1.818   4    932   2.30   4.46   472
 32    4   3.407   3.388   4   1037   1.47   3.91   474
 64    8   6.669   6.768   4   1239   1.46   3.26   478
 16    1   1.143   1.168   5   1227   7.68   4.19   467
 32    2   1.926   1.991   5   1263   3.79   4.06   474
 64    4   3.459   3.517   5   1355   1.88   3.72   478
 32    1   1.172   1.226   6   1499   9.20   4.04   466
 64    2   1.944   1.844   6   1545   2.50   3.91   478
 64    1   1.191   1.133   7   1897   6.82   3.72   470
                               ------------------
                       Mean    1079   3.31   3.72
                         SD     386   3.01    .52
Condition:       Trackball-Pointing                 MT = 155 + 231 ID
Formulation:     Fitts                              r = .9781
Target Width:    W                                  SE = 83.1 ms

Condition:       Trackball-Pointing                 MT = -1.2 + 262 ID
Formulation:     Fitts                              r = .9778
Target Width:    We(SD)                             SE = 83.7 ms

Condition:       Trackball-Pointing                 MT = 197 + 271 ID
Formulation:     Shannon                            r = .9823
Target Width:    W                                  SE = 74.7 ms

Condition:       Trackball-Pointing                 MT = 75 + 300 ID
Formulation:     Shannon                            r = .9809
Target Width:    We(SD)                             SE = 77.7 ms



Condition: Trackball-Dragging

  A    W  We(SD)  We(DE)   ID    MT   Errors   IP  Trials
---------------------------------------------------------
  8    8   7.654   8.522   1    576   5.24   1.81   474
  8    4   4.572   4.832   2    725   8.72   2.83   470
 16    8   7.694   8.762   2    694   5.92   2.96   474
  8    2   2.778   2.907   3    944  15.51   3.24   471
 16    4   4.799   5.122   3    877  10.66   3.50   470
 32    8  10.603  10.733   3   1050  12.35   2.90   465
  8    1   2.244   1.697   4   1179  22.32   3.46   472
 16    2   3.424   2.949   4   1104  16.11   3.69   465
 32    4   7.918   6.052   4   1205  17.20   3.36   465
 64    8  16.164  11.341   4   1447  14.50   2.79   451
 16    1   2.396   1.699   5   1392  22.40   3.67   466
 32    2   5.391   2.979   5   1455  16.54   3.51   457
 64    4  10.023   5.858   5   1617  15.82   3.11   456
 32    1   4.845   1.840   6   1711  26.14   3.57   460
 64    2   7.987   3.104   6   1975  18.30   3.08   443
 64    1   7.440   1.792   7   2295  24.88   3.11   460
                               ------------------
                       Mean    1265  15.79   3.16
                         SD     476   6.24    .47
Condition:       Trackball-Dragging                 MT = 137 + 282 ID
Formulation:     Fitts                              r = .9673
Target Width:    W                                  SE = 125.0 ms

Condition:       Trackball-Dragging                 MT = -255 + 510 ID
Formulation:     Fitts                              r = .9038
Target Width:    We(SD)                             SE = 210.8 ms

Condition:       Trackball-Dragging                 MT = 184 + 331 ID
Formulation:     Shannon                            r = .9749
Target Width:    W                                  SE = 109.7 ms

Condition:       Trackball-Dragging                 MT = -349 + 688 ID
Formulation:     Shannon                            r = .9226
Target Width:    We(SD)                             SE = 190.1 ms