noun phrase · academic
null hypothesis
UK/nʌl haɪˈpɒθəsɪs/US/nʌl haɪˈpɑːθəsɪs/NULL hy·POTH·e·sis
the default assumption that there is no effect or no difference between groups being tested
Examples
“In clinical trials researchers often try to reject the null hypothesis that the new drug is no better than placebo.”
“Failing to reject the null hypothesis does not prove it true, it only means the data do not show strong evidence against it.”
“Statistical tests estimate how likely observed results are if the null hypothesis were true.”
Band 8 sentence
“In hypothesis testing the focus is typically on whether the data provide sufficient evidence to reject the null hypothesis in favour of an alternative.”
Collocations
- reject the null hypothesis
- fail to reject the null hypothesis
- test the null hypothesis
Word family
Common mistakes
accept the null hypothesis→fail to reject the null hypothesis
null theory→null hypothesis
Say it for a higher band
5no-effect hypothesis→6zero hypothesis→7+null hypothesis
Synonyms
no-effect hypothesis
Easily confused
alternative hypothesis
“The alternative hypothesis proposes that the new teaching method improves test scores.”
Related words
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