null hypothesis

In statistics, a null hypothesis is a hypothesis set up to be nullified or refuted in order to support an alternate hypothesis. When used, the null hypothesis is presumed true until statistical evidence in the form of a hypothesis test indicates otherwise. In science, the null hypothesis is used to test differences in treatment and control groups, and the assumption at the outset of the experiment is that no difference exists between the two groups for the variable being compared.
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a statement to be tested that is usually expressed in a negative (or null) way and suggests that no difference or effect is expected. If the statement is disproved, then the null hypothesis is rejected and the alternative hypothesis is accepted.

Null hypothesis
(Econ) Giả thiết Không.+ Trong những kiểm định giả thuyết, đó là giả thiết mà trong đó thống kê kiểm định sẽ dựa vào một hàm phân phối xác suất cho trước.
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