mayacakmak
commented
4 years ago Based on discussion with Kavi during meeting on Jul 23, Thu.
We'd like to systematically vary four variables. For each variable we propose the following values.
- Position distance (dist_xy). Create a grid of the screen where groups of grid cells are at equal distance from the center (starting point of the object being moved). For each distance randomly select cell from that group. Note that the grid needs to have a buffer around it to allow the manipulation interface to fit. A 3x5 grid allows for 5 distance groups (including zero), however some groups are not equally distributed due to the screen being rectangular rather than square.
Instead we could imagine a 5 by 5 grid at the center of the screen, leaving larger buffers on the sides compared to top/bottom.
Illustrations here: https://docs.google.com/presentation/d/1XOFJU3b2MvQ5-VBSauC5McdfJ62DB-ecwA4WOWg2ZXY/edit?usp=sharing
- Rotation distance (dist_theta)
Between 0 and 180, should be 45 degrees -> 5 target angles (if we include 0). For each angle randomly select sign (+/-).
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Target position size/flexibility (thresh_xy): Three levels (1) zero, (2) 1/2 of max (3) max. Max size should be based on grid size determined based on choice of dist_xy and our screen size.
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Target rotation size/flexibility (thresh_theta): Three levels (1) zero, (2) 1/2 of max (3) max. Max size should be based on grid size determined based on choice of dist_theta (45 degrees).
Random noise: The noise added to dist_xy and dist_theta should be smaller than max_xy and max_theta (45). The noise added to dist_xy should be applied in a random direction sampled between 0-360 degrees to select the actual x,y position of the target. The noise added to thresh_xy and thresh_theta should be within 1/4 of max_xy and max_theta
There should be meaningful difference between the different threshold values, otherwise might be worth increasing screen size.
We should ensure dist_xy=0 and dist_theta=0 does not happen at the same time (object already at target). Further the thresh_xy and thresh_theta should not involve the initial object pose.
We should ensure the target is visible (not hiding behind manipulation controls).
With the above proposal we have 5x dist_xy, 5x dist_theta, 3x thresh_xy, 3xthresh_theta, which results in 225 different unique configurations. This would require splitting the full set of configurations across participants, and further large sample size to get good coverage through the random noise.
A reduced proposal such that all configurations can be covered by a single participant could be 3x dist_xy, 3x dist_theta, 2x thresh_xy, 2xthresh_theta, resulting in 36 configurations. The intermediate values would be covered through the random noise variations across participants. This proposal might result in a more balanced individual experience.
kavidey
For some reason when the EE goes below the target, it doesn't count as a correct position:
The practice screen randomly specifies the target after each trial. For the systematic data collection we need to systematically vary:
We need to keep the total duration of the experiment within a certain range to avoid fatigue, so we can decide how many variations of each of these we want to do based on how long a single session tends to take for the slowest interface.
Sampling variations: Rather than having fixed/exact variations we might want to have a complete set of exact options and add a little bit of noise to everything (center_x, center_y, center_theta, thresh_xy, thresh_theta => note that the variations are in terms of dist_xy, dist_theta, thresh_xy, thresh_theta, but noise in the former would result in less recognizable patterns).