Hello, Is this correct: Cross-sectional data is when we observe different subjects within some time period (a year, 5 year period, etc.). E.g. household income within 5 year period. Right? Time series data is when we observe differenet subjects for each time unit (every week, every year). E.g. houshold income for every year. Right? Now, could someone please explain (plain and simple) what is cross-sectional pooled data, time-series pooled data, panel data, followed with an example? On the Internet are various deffinitions, and I'm a little bit confused know.:confused::confused: Please help. Big thanks. Best regards.