Hiroshi Ashida just suggested that to me too - you're both right. The effect appears to be due to a depth order effect so has nothing to do with the implied perspective. When the lines both extend across the triangle borders (and thus look like they are in front of it) the depth percept disappears:

What would happen if you make both lines extend over the illusory border? If the depth effect is due to border ownership assignment, the effect should disappear or weaken.

We are using the OptiTrack, it has an Unity plugin, but I don’t have experience with it.

optitrack.com

www.ndigital.com/products/leg...

In any case, the NDI Optotrak was discontinued more than 5 years ago. Since then we have moved to another motion capture system.

This code only loads data from an Optotrak tab- or comma-separated values file, it doesn’t give you any control about the data collection part.

This could be helpful to make it work: github.com/ha5dzs/motom...

Quartiles can be estimated in many different ways. For example, R provides 9 different types, see here stat.ethz.ch/R-manual/R-d... and here en.wikipedia.org/wiki/Quantil...

And you can conveniently lay your eye in the glass cylinder during the experiment.

The problem (maybe) is that there are no two unique groups. Every participant could be labeled as A or B.

Maybe I’m misunderstanding something, but you can simply calculate the correlation for each dyad separately and you don’t need lme4. Correlation is a symmetric measure, so it doesn’t matter if you correlate A with B or B with A.

Are A and B heartbeat data of a bunch of participants in two tasks/conditions or are they data from a pair of participants?

The Satterthwaite method calculates df by balancing the estimated variability of fixed and random effects. Higher variability, especially in random effects, reduces the precision with which fixed effects are estimated, leading to lower df.