Formula to calculate precision

Answer 1

It will depend what operation you use to calculate your value.

First you check the uncertainty of your instruments.

Then

If you add or subtract two values, you add the uncertainty (even when you subtract)

If you multiply or divide, you do the following formula.

dZ=(dx/x+dy/y)*z

dz: uncertainty of your final value

z is your value

dx is the uncertainty of your first value

x is the value of you first value

similarly for y which is you second value

Answer 2

Precision is calculated using the formula: Precision = True Positives / (True Positives + False Positives). True Positives are the correctly predicted positive instances, while False Positives are the incorrectly predicted positive instances. Precision measures the proportion of correctly predicted positive instances out of all instances predicted as positive.