LI JIN and D'ARCY COOLICAN, Partners at Andreessen Horowitz, share 16 different ways to look at and evaluate product network effects: Key Quote "For two-sided marketplaces matching supply and demand, pay special attention to the marketplace and unit economics sections; for social networks (including workplace ones), what matters most is engagement and activity. In the end, though, it all comes down to the very definition of network effects: whether your product becomes more valuable as more people use it." User acquisition metrics Direct side network effects. The organic share of new users should increase as people enlist their friends to join the network. Measure with organic vs. paid user growth. Growing a strong internal network. A strong network will generate more traffic and engagement on its own and not be reliant on external sources. Measure with sources of traffic. Falling Customer Acquisition Costs. As networks grow, it should be easier and less expensive to acquire a new user, though this is highly market dependent.