preparing r-studio project
Loading and Cleaning

* unzip & load
* convert `interval` to `time`string
* convert `date`and `time` to proper `datetime`
* drop superfluous columns
we might need some columns for ease of use
steps per day

* calculation
* histogram
* summary
use aggregate, since it handles NAs better
daily activity pattern

* averaging over all days
* time series plot
* maximum activity
to load data analogous into local workspace
impute strategy

* count Nas
* devise strategy
imputed data

* do imputing
* compare findings
imputed finalized

* comparing plots
* conclusion
weekday/weekend comparison

* produce discriminating factor
* average using it
* plot comparison graph
* describe findings