The phrase "uncontrollable variables" is correct and usable in written English.
It refers to factors or elements that cannot be controlled or predicted in a situation or experiment. Example: The results of the study were affected by several uncontrollable variables, such as weather conditions and participant motivation.
This paper focuses on uncontrollable variables' effects on multiunit restaurant productivity using data envelopment analysis (DEA).
It is easier for analysts to forecast earnings if they know that uncontrollable variables won't affect the numbers.
They estimate uncontrollable variables as best they can, and a strategy is then developed to achieve the company's objectives.
Blocking is an important technique to reduce the noises introduced from uncontrollable variables.
The effects of permeability and acid solubility were incorporated into an overall correlation that combines the effects of controllable and uncontrollable variables.
I enjoy cleaning because life is full of uncontrollable variables, and having a clean living space is one thing you can (for the most part) control.
In Table 2, one block was introduced because no uncontrollable variable has been detected.
Weather may be the ultimate uncontrollable variable, but it's a mean-reverting phenomenon if ever there was one.
In the absence of any other scientific observations, this result could indicate poor test conditions, e.g. a sludge inoculum with a microbial community poorly suited to the degradation of this substance; however, this is an uncontrollable variable which contributes to the overall variation associated with this test method.
Since we observed a significant increase of cortical excitability after ECT in each and every patient, despite the reduced sample size, we believe it is very unlikely that an unknown and uncontrollable variable other than ECT would have been able to significantly modulate TEPs consistently across patients.
We argue the importance of first considering managerially uncontrollable (nondiscretionary) variables as inputs in the actual DEA model, with managerially controllable variables considered post hoc for their relationship to the efficiency scores.
