"a fair proxy" is correct and usable in written English.
You can use it when you are referring to a representation or substitute for something else. For example, "We use a fair proxy for the original material in our experiments."
The stock market used to be a fair proxy for the state of the economy.
Thus the smoking rate for the state as a whole may be a fair proxy for the county smoking rate.
She drew her data from the United States Patent and Trademark Office (USPTO)—not a perfect indicator of inventiveness, but probably a fair proxy for it.
But as the contrasting fortunes of forests (a fair proxy for biodiversity) on the Korean peninsula and Hispaniola suggest, it is not so much growth as poverty that reduces biodiversity.
This included a study of where MPs went to school, which seems like a fair proxy for whether their backgrounds were the sort of blue collar worker families Robert Halfon and co are talking about, or not.
That's probably a fair proxy for their share of the digital market, at least in terms of new issues.
Because food service workers represent 44percentt of all minimum wage earners, this series is a pretty fair proxy for the productivity gains of minimum wage workers.
Shareholders could always try to take matters into their own hands and force the corporation to adopt fair proxy access rules but that rarely happens because of the myriad ways that corporations can prevent changes to their by laws by shareholders.
Among the selected measures evaluated, surgical complexity and case complexity are only fair proxies for CMI, while surgical proportion was a poor proxy for CMI.
CPT complexity and ICU/Ventilator use are fair proxies for case mix index (CMI-ICDC), but surgical proportion is a poor proxy.
Both CPT complexity and ICU/Ventilator use are fair proxies for CMI, suggesting the possibility to use the first two measures as intermediate measures of CMI, or more ideally as separate measures altogether, which could inform contracting as hospital process indicators.
