Column 2: evidence · screens against sleep
Open data, followed all the way down to one person inside it.
Every piece here starts with a public dataset and ends with a story. The numbers can be checked: any figure set in mono opens its own evidence in a column to the right, so you never have to leave the sentence you are reading to find out whether it is true.
open to work
work
files
Every correlation is with the 21-item questionnaire total, on the same 4,810 teenagers. r² is the share of the differences between them that the measure accounts for.
Sleep quality accounts for 8× the variance screen time does.
how much of the screen effect travels with sleep
| held constant | screen × it | partial r | absorbed |
|---|---|---|---|
| avg_sleep_hours | −0.2563 | +0.0725 | 46% |
| midsleep_weekend_hours | +0.2865 | +0.0968 | 27.9% |
| sleep_quality_index | +0.0923 | +0.1078 | 19.8% |
| social_jetlag_hours | +0.1820 | +0.1237 | 7.9% |
Starting from +0.1344. Holding hours slept constant absorbs 46% of it. This is a decomposition, not a causal claim — see the limits note on the piece.