## PSY 3520 W1 Assignment 3 Hypothesis

*PSY 3520 W1 Assignment 3 Hypothesis*

A hypothesis (plural hypotheses) is a precise, testable statement of what the researcher(s) predict will be the outcome of the study.

This usually involves proposing a possible relationship between two variables: the independent variable (what the researcher changes) and the dependent variable (what the research measures).

In research, there is a convention that the hypothesis is written in two forms, the null hypothesis, and the alternative hypothesis (called the experimental hypothesis when the method of investigation is an experiment).

#### Types of Research Hypotheses

**Alternative Hypothesis**

The alternative hypothesis states that there is a relationship between the two variables being studied (one variable has an effect on the other).

It states that the results are not due to chance and that they are significant in terms of supporting the theory being investigated.

#### Null Hypothesis

The null hypothesis states that there is no relationship between the two variables being studied (one variable does not affect the other).

It states results are due to chance and are not significant in terms of supporting the idea being investigated.

#### Non-directional Hypothesis

A two-tailed non-directional hypothesis predicts that the independent variable will have an effect on the dependent variable, but the direction of the effect is not specified.

E.g., there will be a difference in how many numbers are correctly recalled by children and adults.

#### Directional Hypothesis

A one-tailed directional hypothesis predicts the nature of the effect of the independent variable on the dependent variable.

E.g., adults will correctly recall more words than children.

#### How to Write a Hypothesis

1. To write the alternative and null hypotheses for an investigation, you need to identify the key variables in the study.

The independent variable is manipulated by the researcher and the dependent variable is the outcome which is measured.

- 2. Operationalized the variables being investigated.Operational variables (or operationalizing definitions) refer to how you will define and measure a specific variable as it is used in your study.
- 3. Decide on a direction for your prediction. If there is evidence in the literature to support a specific effect on the independent variable on the dependent variable, write a directional (one-tailed) hypothesis.If there are limited or ambiguous findings in the literature regarding the effect of the independent variable on the dependent variable, write a non-directional (two-tailed) hypothesis.
- 4. Write your hypothesis. A good hypothesis is short (i.e. concise) and comprises clear and simple language.