What is the purpose of a hypothesis?
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In research, a hypothesis purpose is to make a statement of the expected results of the study being conducted and makes predictions on how to or more contructs will be related. The hypothesis is there to serve as a basis for the study to pose a question that can be tested in future research. Every experiment actually has two hypotheses: the null hypothesis and the alternative hypothesis. The null hypothesis is the default position that there is no relationship between the two things being studied, and the alternative hypothesis is that there is some relationship between them.
Example / Application
Application: The hypothesis in the Duncan principle is that the more power lost by the ego, the more drastic the outburst of the subject when it has reached its breaking point. They will prove this by provoking the test subjects to frustration by constantly pretending that the test will have to be postponed by 5 more minutes. The importance of the hypothesis and its purpose is to pose the prediction that most subjects will not continue, this is disproven as we see the last participant stay for 26 hours putting into question the validity of any previous research.