The Klout score measures influence based on a person’s ability to drive action. It uses data from social networks to generate a ranking. The service recently announced an update to the factors in the scores.
The stability and accuracy of scores is improved, and subscores become more clear.
True Reach is the number of people influenced based on connections.
Amplification is a measure of f=degree of influence — how many people in the potential audience act upon content.
Network Impact is the influence of the audience. This is on a 1 to 100 scale and indicates the influence level of people who engage with content.