Information can be obtained from multi-level data by examining both the group-level and individual-level data matrices.
Household survey
This e-book only deals with analysis of a single data matrix. State that information in multi-level data can be transferred from one level to the other:
Select variables from the pop-up menu to see whether they are copied from the top-level data matrix to the sub-level matrix or summarised from the sub-level data matrix to the top-level one.
Explain that properly analysing multi-level data can be tricky:
These data are typical of information that is collected in surveys of consumer purchases and attitudes. A sample of houses is selected and information is collected from all individuals in these houses.