"counter assumptions" is correct and usable in written English.
You can use it when you want to express the idea of bothering or questioning something that is assumed or expected to be true. For example, "Her counter assumptions took the audience by surprise."
Experimental errors were estimated for both cases of statistically independent measurements and counter assumption.
"I like countering assumptions," Ms. Slemmons said in an interview at her studio in Chicago.
She has spent her life countering assumptions, including in the media, that she must be a Muslim.
[Bloomberg News] Countering assumptions, the most thorough study to date on the effects of biofuel production from West Coast forests indicates that it would increase carbon dioxide emissions from those forests by at least 14 percent — and that's if the efficiency of the operations is optimal.
And for every assumption about what the new line's effect will be, there is a counter-assumption.
For every assumption about what the new line's impact will be, there is a counter-assumption.
"The counter-assumption tends to be, once a historical account is conscientiously done by a so-called objective observer, it is definitive," Mr. Duberman said.
Clearly, a voice of reason and firmness was essential here to counter such assumptions.
Having secured a senior position within an organisation through effort and ability, many mums therefore feel pressured into working harder than ever to counter such assumptions.
Similarly, a survey showing that in 1997 both fathers and mothers spent significantly more time with their children than they did in 1981 made front-page news a couple of weeks ago, presumably because it seemed to counter common assumptions.
