In an epidemiological context, the typical motivation behind estimating mathematical model parameters is to check whether the mathematical framework includes all necessary mechanistic features, and to enable the prediction of spreading dynamics in the future given what has already occurred. The distinction in spreading behaviours supports the view that there is more to clinical depression than simply low mood. Depression and other mood disorders are a growing affliction upon modern society, with considerable losses in global health and functioning. The mood-specific data needed to be combined with information on how many friends everyone initially had and their personal mood status. When working with two waves of data, the presence of homophily and shared context mechanisms will simply lead to more instances of individuals having the same mood state as their friends. The memoryless property means the mood state at the next time step depends only on the current state, with the sequence of events that preceded it having no influence.