The data has been collected hourly at three locations across Kampala (US Embassy, Makerere, Nakawa - this data is very unbalanced in ratio of approx 4:2:1) over differing time periods in the last two years.
There should be no NaNs in the PM data although the temp and humidity may have some minor gaps.
The target is the reference value. A reference monitor is a very heavy (30kg) static machine that requires mains electricity and secure mounting. It is not portable so once it's in place there it will stay. It measures PM2.5 (that is the mass of particulate matter smaller than 2.5 microns, or 1/30th the thickness of a human hair, that is found in a cubic metre of air) with incredible accuracy accepted at international standards.
We collocated one of our low cost devices next to each of these devices at the same height, less than 1m apart. A low cost device measures PM2.5 as above but also PM10 (this captures particulate matter smaller than 10 microns in diameter, that is ⅓ the thickness of a human hair, so includes much bigger particles but also includes PM2.5 values. Low cost monitors contain two identical sensors so you will see two values for PM2.5 and two values for PM10. In an ideal world these sensors would record identical values but some variation is expected. Two are used as a backup and as a check.
We also include temperature and humidity values, there are several weather stations located across Kampala and analysis has shown that variation between these values is minimal so the same value will be found at the same time across each of the locations.
We also include metadata about the latitude and longitude, altitude, terrain features, greeness, distance from a major road which you may find useful. This value does not change for the same location over time but is included in de-normalised format for ease of use.
The objective of this challenge is to develop a model that will take low cost device data and other supplementary data and transform it as accurately as possible to the reference value.
Files available for download: