1. Estimator Variable
Estimator variable is the factors that can't be controlled by criminal justice system, as it usually happens on the crime scene. It is practically impossible to control this variable.
2. System Variable
System variable is the factors that can be controlled by criminal justice system. Usually revolves around factors involved in the retrieval phase or when the crime has already done and the witness are asked for testimony by criminal justice system.
A great division of how eyewitness testimony can be broadly divided into two parts.
It's a fantastic starting place, from which we can start to assign circumstances.
For instance if questioning influences eyewitness testimony, by what you've laid out that would be an example of a System Variable.
Given the already tumultuous unreliability of eyewitness testimony as pointed out by Loftus, I guess we have to focus on reducing the number of possible infuences that fall under the category of a system variable.
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