I want to analysis US-EPA data, there data are cross section and time series (2016-2018), what method i should do for that ?

I just have some variables, there are : country, state, year, days with AQI, Good Days, Moderate Days, Unhealthy for Sensitive Groups Days, Unhealthy Days, Very Unhealthy Days, Hazardous Days,...

03 March 2019 1,547 1 View