Thank you so much for granting me access to the datasets.
This site looks great, the tools available are really helpful, and it's nice to be part of a forum of people who are interested in sleep as well!
I have a question regarding the staging annotations. In the CSV files provided (https://sleepdata.org/datasets/shhs/files/annotations-staging/shhs1), what does the time variable "epoch" refer to?
My guess is that each "epoch" corresponds to a 30 second-window, since there seem to be ~1000 "epochs" in each file, which corresponds to ~8h of sleep, average for most people.
This guess was confirmed by the fact that when I view the EDF data in the browser (https://sleepdata.org/datasets/shhs/files/polysomnography/edfs/shhs1), the default window is 30 seconds long.
It would be great if one of the core members could confirm this.
Thanks a lot!
Thanks for checking out the site!
I can confirm that the epochs in the SHHS sleep staging annotations correspond to 30-second windows. This is also correct for other datasets that we currently have EDF and XML annotation files posted for.
For SHHS, I found mention of using the 30-second windows for scoring deep within one of the manuals: https://www.sleepdata.org/datasets/shhs/pages/mop/6-610-mop-overview-of-scoring.md
Thank you so much for your prompt response!