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# 3.1 Non-directional hypotheses

Non-directional hypothesesalso known as two-tailed hypotheses, form the basis for open-ended investigations. Decision-makers use these hypotheses, which employ equal (=) or not equal (≠) signs, when they do not predict a specific direction for the relationship or difference under study. This approach proves particularly useful in exploratory research or when examining complex phenomena, allowing decision-makers to study relationships between variables without preconceived notions.

Non-directional hypotheses aim to determine whether a statistically significant difference or relationship exists between two or more variables. The term "two-tailed" refers to the statistical test used to evaluate the hypothesis, which considers the possibility that the difference or relationship could occur in either direction.

A non-directional hypothesis typically comprises two components:

- The null hypothesis (H0): This usually states that there is no difference or relationship between the variables being studied.

- The alternative hypothesis (H1): This suggests that there is a significant difference or relationship, but does not specify the direction of this difference or relationship.

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OpenLearn - Data analysis: hypothesis testing
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