What is the difference between a one-tailed and two-tailed hypothesis? How Would you operationalise a hypothesis?

A one-tailed hypothesis predicts the direction of the results, whereas a two-tailed hypothesis does not. A two-tailed hypothesis simply states there will be an effect of the Independent variable on the dependent variable. To operationalise a hypothesis, the IV and DV need to be specific and clearly identified. E.g.Boys are more aggressive than girls —> 12 years old males will score more highly on an aggression questionnaire than 12 year old females.