Aims hypotheses, IVs and DV's

• The independent variable (IV) in an experiment is the variable that the researcher manipulates and which is assumed to have a direct effect on the dependent variable (DV).
• The dependent variable (DV) in an experiment is the variable that the research measures.
• The dependent variable (DV) in an experiment is the variable that is affected by changes in the independent variable (IV).
• A hypothesis is a clear and precise prediction about the difference or relationship between the variables in the study.
• A directional hypothesis predicts the specific nature (direction) of the difference between two or more variables.
• A directional hypothesis is based on past research, accepted theory or literature on the topic.
• A directional hypothesis is sometimes called one-tailed.
• Examples of key words used in a directional hypothesis are: higher, lower, more, less, increase, decrease, positive and negative.
• A non-directional hypothesis predicts that a difference will exist between two or more variables without predicting the exact direction of the difference.
• A directional hypothesis is used This is because previous research has been inconclusive, and the specific nature (direction) of the effect of the IV on the DV cannot be predicted confidently.
• A non-directional hypothesis is sometimes called two-tailed.
• a non-directional hypothesis just state there will be a difference.
• a null hypothesis states there will be no difference or correlation between the vairbales, once all the data is collected and analysed they accept one hypothesis and reject the other
• To wite a hypothesis for a correlation state if the will be a negative or postive correlation between the variables
• Aim = to examine the effects of …….
• ·       A pilot study is a small-scale trial run of a study that is carried out before the main study

  ·       They are used to determine whether the research design works or not with a view to making improvements
• The aim is the intended purpose of a psychological investigation