modified equation to reflect equation psychos are using

2021-12-09 18:45:43 +00:00
parent 6cacdee082
commit aaf27ab7bd
1 changed files with 1 additions and 1 deletions
--- a/app/lib/irt/item_information_function.py
+++ b/app/lib/irt/item_information_function.py
@ -11,7 +11,7 @@ class ItemInformationFunction():
    if self.model_data.model == '3PL':
      p = ThreeParameterLogistic(self.model_data, kwargs).result()
      q = 1 - p
-      return self.model_data.a_param**2 * ((q / p) * ((p - (self.model_data.c_param**2)) / (1 - (self.model_data.c_param**2))))
+      return (self.model_data.a_param * q * (p - self.model_data.c_param)**2) / (p * ((1 - self.model_data.c_param)**2))
    else:
      # potentially error out
      return None