Variables, aims and hypotheses

• What is an experiment in research?

  Investigating the effect of one variable on another
• What are the two main variables in psychological studies?

  Independent variable and dependent variable
• What is an independent variable (IV)?

  A variable thought to bring about change
• How might an experimenter manipulate the IV?

  By changing how information is presented
• What is a dependent variable (DV)?

  The result measured in an experiment
• Why is it vital to see the direct effect of the IV on the DV?

  To ensure scientific validity of the results
• What are extraneous variables?

  Variables that may influence the dependent variable
• What happens if extraneous variables affect the DV?

  They create confounding variables that distort results
• What is the aim of a study?

  A general statement about the study's purpose
• How do aims typically begin?

  With the words 'to investigate…'
• What is a hypothesis?

  A testable prediction about a study's outcome
• What distinguishes a directional hypothesis?

  It predicts the specific outcome of the results
• What is a non-directional hypothesis?

  It states there is a difference without specifying direction
• What must all hypotheses be?

  Fully operationalised and specific
• What does operationalising a variable mean?

  Defining it clearly for measurement
• How would you operationalise 'aggression' in a study?

  By defining and measuring specific aggressive behaviors
• What are the types of aggression that can be measured?

  • Verbal aggression: swearing, shouting, name-calling
  • Physical aggression: hitting, spitting, kicking
• What does an alternative hypothesis state?

  The IV will affect the DV
• What is a directional hypothesis in experiments?

  It predicts a specific effect of the IV on the DV
• What is a non-directional hypothesis in experiments?

  It states the IV will affect the DV without direction
• What is a null hypothesis?

  It predicts the IV will not affect the DV
• How do hypotheses for correlations differ from those for experiments?

  They involve co-variables instead of IV and DV
• What does a non-directional hypothesis in a correlation state?

  There will be a relationship without specifying direction
• What are the key components of a hypothesis?

  • Must be testable
  • Should specify the IV and DV
  • Must be operationalised
• What does a directional hypothesis in a correlation state?

  There will be a specific type of relationship