Is there a way to measure how much time was spent on the left and the right side of the y-axis using mousetrap? I'm almost done with my analysis, but I haven't stumbles upon such a measure yet.
within the mousetrap package, there is no standard measure for that. However, you could compute it with the following code:
library(mousetrap)
# Use example data from mousetrap package
mt_data <- mt_example
# Compute derivatives to make timestamp differences accessible
mt_data <- mt_derivatives(mt_data, return_delta_time = TRUE)
# Compute time spent for positive x values (i.e., right of y axis)
mt_data$data$time_x_positive <- rowSums(mt_data$trajectories[,,"delta_time"]*(mt_data$trajectories[,,"xpos"]>0), na.rm = TRUE)
# Compute time spent for negative x values (i.e., left of y axis)
mt_data$data$time_x_negative <- rowSums(mt_data$trajectories[,,"delta_time"]*(mt_data$trajectories[,,"xpos"]<0), na.rm = TRUE)
Note that the time exactly on the y axis (i.e., for x = 0) is excluded. In addition, since you require the time which is a difference measure between two time stamps, it is somewhat arbitrary how these time differences are assigned to the positions (i.e., whether they are shifted forwards or backwards - they are shifted forward within the mt_derivatives function, see documentation: http://pascalkieslich.github.io/mousetrap/reference/mt_derivatives.html#details-1). However, this is just a minor technical detail.
Comments
Hi Sara,
within the mousetrap package, there is no standard measure for that. However, you could compute it with the following code:
Note that the time exactly on the y axis (i.e., for x = 0) is excluded. In addition, since you require the time which is a difference measure between two time stamps, it is somewhat arbitrary how these time differences are assigned to the positions (i.e., whether they are shifted forwards or backwards - they are shifted forward within the mt_derivatives function, see documentation: http://pascalkieslich.github.io/mousetrap/reference/mt_derivatives.html#details-1). However, this is just a minor technical detail.
Best,
Pascal