"Being a first-time father kept me so preoccupied for a few years that I didn't really bother thinking about the downstream effects of not keeping in touch with anyone, " Spenser says.

CNN: Five ways to refresh your outdated network

Second, mix models measure immediate effects within a single week with no linkage to any other weeks in order to capture the downstream consequences of the immediate effects.

FORBES: The Downside Of Marketing Mix Models Is There's No Upside For CMOs