This unit has covered various analytical techniques and methods of data management associated with hierarchically structured data, i.e. data at both the micro and macro levels. These have started with the kinds of research questions that require linked micro and macro data, assessing micro data for variation between macro units, linking micro and macro data, weighting linked micro and macro data, checking the quality of micro data with macro data and adjusting weights to account for discrepancies, and basic approaches to the analysis of linked micro and macro data. Unit 5 moves on from this unit by introducing multilevel modelling which is explicitly designed for hierarchical data of which linked micro and macro data is an example.