Why are they reporting correlations as percentages? That's incredibly misleading. If one wants a more intuitive measure of concordance than the correlation, one

Why are they reporting correlations as percentages? That's incredibly misleading. If one wants a more intuitive measure of concordance than the correlation, one could use the coefficient of determination, which is the correlation squared. This number tells you the percentage of the variation that is accounted for by the tracker. For a deeper introduction to correlations, see e.g. [1]. Let's rewrite the summary with the correct figures (and reduce the ridiculous number of sigfigs): > The analysis reveals that commonly worn fitness trackers are the most accurate for measuring heart rate, providing a strong accuracy of 58 %. However, they are only moderately accurate for tracking step count and energy expenditure, 47 % and 32 %, respectively. The highest level of accuracy is provided by the Apple Watch, which exhibits 74 % accuracy for heart rate and 50 % for energy expenditure. Garmin is the most accurate for tracking step count, as it offers 68 % accuracy. ---- [1]: https://entropicthoughts.com/the-surprising-richness-of-correlations https://entropicthoughts.com/the-surprising-richness-of-corr...