mousetrack (version 1.0.0)

getmouseDV: Get Mouse Dependent Variables

Description

Mother function of the package, which computes from 2D (x, y) mouse-tracking trajectories, dependent measures characterizing the underlying action-dynamics patterns.

Usage

getmouseDV(x, y, t, unit, counterb, refcounterb,
dwellfin, velajbin, escape, escapeinit)

Arguments

x

x-coordinate point of the trajectory

y

y-coordinate point of the trajectory

t

a vector with time indexes

unit

the sampling unit, expressed in milliseconds

counterb

the position of the yes-no response button

refcounterb

the position of the yes-no response button, which we want to use as reference to transpose all trajectories on the same side of the display

dwellfin

Region (in pixels) around response button where measures of dwell are computed

velajbin

Number of timesteps used to average velocity

escape

Amount of pixels to escape when trimming the trajectory

escapeinit

Region around origin (in pixels) in which initial angle is measured

Value

It returns a list with 40 DVs:

DVtotaltime

The total duration of the trajectory

DVlatency

The latency of the start of the movement

DVinmot

The total time of motion

DVdwell

The dwell time to commit to a final response

DVdist

Euclidean distance of the trajectory

DVdistinmot

Distance traveled outside of the escape region

DVvelmax

The maximum velocity reached

DVvelmaxstart

The latency when maximum velocity was observed

DVaccmax

Maximum acceleration

DVaccmaxstart

The latency when maximum acceleration was observed

arclengthtotal

The length of the arc subtending the trajectory after motion was initiated

maxpathoff

Maximum offset of the trajectory

DVxflplat

Change in x-direction after escape region: latency

DVxflpmot

Change in x-direction after escape region: in motion

DVafllat

Change of angle-flipping in the dweel region: latency

DVaflpmot

Change of angle-flipping in the dweel region: in motion

DVxflpdwl

Change in x-direction in dwell region

DVaflpdwl

Change of angle-flipping in dwell region

DVxe

Entropy along x-axis (default 5 time-points)

DVxse

Entropy (standard error) along x-axis (default 5 time-points)

DVye

Entropy along y-axis (default 5 time-points)

DVyse

Entropy (standard error) along y-axis (default 5 time-points)

DVae

Entropy along angle-trajectory (default 5 time-points)

DVase

Entropy (standard error) along angle-trajectory (default 5 time-points)

trajang

Angles tangent to the trajectory

DVAUC

Area under the Curve

DVmaxpull

Maximum pull towards the incorrect response button

DVmaxpullstart

Latency of pull towards incorrect response button

DVmaxang

Maximum severity of angle towards incorrect response button while in motion

DVmaxangstart

Time-point where maximum severity of angle was observed.

DVinitang

The angle of trajectory after escaping region in absolute value

DVmaxx

Maximum x-value observed

DVminx

Minimum x-value observed

DVmaxy

Maximum y-value observed

DVminy

Minimum y-value observed

OLnegmove

Percentage of trajectory not moving towards incorrect response, i.e., negative y values

OL1

Binary value indicating whether motion time was longer than latency

OL2

Binary value indicating whether maximum velocity was inside the latency region

OL3

Binary value indicating whether maximum acceleration is inside the latency region

OL4

Binary value indicating whether trajectory travels in negative y-values after escaping the latency region

References

Spivey, M., and Dale, R. (2006). Continuous dynamics in real-time cognition. Current Directions in Psychological Science, 15(5), 207-211. Freeman, J. B., and Ambady, N. (2010). Mousetracker: Software for studying real-time mental processing using a computer mouse-tracking method. Behavior Research Methods, 42(1), 226-241.

Examples

data(mousemove)
unit = 25; dwellfin = escape = escapeinit = 100
velajbin = 6

x = mousemove$x; y = mousemove$y;
counterb = as.character( mousemove$counterb[1] )
refcounterb = "R"
t = mousemove$time

ans =  getmouseDV(x, y, t, unit, counterb,
        refcounterb, dwellfin, velajbin,
        escape, escapeinit)

str(ans)