[jruohonen]

As an idea, (1) vs. (2) might be interesting, although you cannot deduce about things like dopamine and I doubt whether consumer-grade physical sensors really convey "emotional states". If you do it, open source and open data would be ideal as the idea might fly also as a research topic.

[jasiek-net]

Thanks, it will start as an open source project, as people may be concern about privacy with such as delicate subject. And I do master studies at psychology so it will be research topic at least for me :)

[jruohonen]

Even if it would be spurious, it would be interesting to see whether there is a correlation. (I used to have a Oura ring out of similar interests, but lost it somewhere someday.) Viz newsrooms see also:

https://news.ycombinator.com/item?id=38779439

[jasiek-net]

For me the most interesting part is mood tracking, as many of the psychological methods are based on self-evaluation and here we have an opportunity to gather data real-time without user input.

Glad you came with oura ring as I though about this project as an oura ring for emotional state.