The phrase "a useful assumption" is correct and usable in written English.
You can use it when discussing a premise or belief that aids in understanding or simplifying a situation or problem.
Example: "In our analysis, we made a useful assumption that the market conditions would remain stable over the next quarter."
Alternatives: "a helpful premise" or "a beneficial hypothesis".
Indeed, much finance and economics research and teaching is built on the silly (though occasionally useful) assumption that man is a rational maximizer of his own utilities -- and that these utilities can be measured financially.
If specific hypotheses regarding differences between participants are of interest, it is possible to test interactions with participants; however, for most analyses, participant as a main effect will be a useful simplifying assumption.
Practically useful assumption of zero normal wall mass flux is imposed.
Everyone can change, but the most useful assumption you can make is that the boss will always be the way she is and that any improvement is going to have to come from your end.
It's very stylized, making some obviously untrue but I think still useful assumptions, and I have been finding that it clarifies my own thinking, at any rate.
In this section, we present some useful assumptions and state several lemmas which will be useful in the proving of the main results.
They also provide a useful way to represent assumptions, especially conditional independence assumptions, necessary for statistical analyses and causal inference.
This approach provides a useful framework with minimal assumptions within which context can be modeled to predict corresponding changes in motor output and behavior.
This assumption provides a useful abstraction in that it lets the task planners focus on what tasks should be done, while lower-level motion planners and controllers take care of the details of how the task should be performed.
The statistical modelling through Bayesian autoregressive assumption appears a useful method to assess the long-run relationship between manufactured and RYO cigarettes.
