Performs point estimate calculation of effort after prep functions. Calculate mean and variance for section_num-period-day_type-angler_final. This is the finest stratification above individual days.
Details
sample size is inherently small for a day_type within week stratification -the var() and sd() functions return NA when passed a length-1 vector (single obs) -variance has limited meaning even when n=3, e.g. if sampling Fri & Sat & Sun BUT sample design itself (and first principles) stratify on day_type such that pooling over weekend/weekday is counter to data collection protocol/design could pool over weeks (and perhaps angler_final) if a better variance is desired over the fishery duration