+ def get_mean(self) -> float:
+ count = len(self.lowers) + len(self.highers)
+ return self.aggregate / count
+
+ def get_stdev(self) -> float:
+ mean = self.get_mean()
+ variance = 0.0
+ for n in self.lowers:
+ n = -n
+ variance += (n - mean) ** 2
+ for n in self.highers:
+ variance += (n - mean) ** 2
+ return math.sqrt(variance)
+