2 <a href=
"https://en.wikipedia.org/wiki/Serial_interval" target=
"_blank"
8 <p>The serial interval (SI) is NOT one of the estimators.
</p>
10 The SI is a parameter required by all of the estimators, and can also be
11 estimated by the WP method.
15 The SI is defined as the average time between successive infections in a chain
16 of transmission i.e., the time between the infection of an infected and their
17 subsequent transmissions.