medical data
by kc320722 - Sunday, May 17, 2015, 12:24:06

Dear organizers, I've got a question about sentence from column_info

 "The aggregations [of the medical data] have a form of basic statistics of the readings computed over a fixed period of time."

 What does "fixed period of time" mean? The same 1.8 sec from which we have acceleratory and gyroscope readings?

Thank you, Konrad

Re: medical data
by krykaczewski - Monday, May 18, 2015, 11:47:32

Dear Konrad,

There was no meaning to use the same time interval to count statistics on it, as these features arrived in different times. For example, ecg changed instantaneously, while rr was changing very slowly (like once per minute). Therefore, we used whole 1.8s interval for ECG and for other qualities we used time delay:

    hr/br = 40s
    rr = 50s
    temp = 30s

In this way, for temperature this interval looked like [t - 1.8s - 30s, t]. Otherwise, training data would be almost constant in wide periods.

I hope this will clarify a little bit.