

YAML is not a good format for this. But any line based or steamable format would be good enough for log data like this. Really easy to parse with any language or even directly with shell scripts. No need to even know SQL, any text processing would work fine.
Cannot remember if the study was stupid or if peoples interpretations of it where. But when covered up else where you will lose a lot of heat through your head. More so then if just an arm or just a leg was exposed as with your arms and legs your body will slow down blood flow through them to try and converse your core temperature - it cannot do that with your head.