Hypotheses

• What is the difference between research aims and hypotheses?

  Aims outline what to investigate; hypotheses state testable predictions
• Why might a researcher choose to investigate a specific aim?

  Previous research raised interesting questions
• How should a researcher phrase an aim?

  As a clear statement or question
• What is a hypothesis?

  A precise statement that can be tested
• What must a hypothesis include in an experiment?

  Independent and dependent variables
• What is the null hypothesis?

  There is no difference between conditions
• When do scientists accept the null hypothesis?

  Unless evidence is strong enough to reject it
• What is the alternate hypothesis also known as?

  Research hypothesis or H1
• What does the alternate hypothesis suggest?

  There is a difference between conditions
• How do researchers use statistical tests in hypothesis testing?

  To analyze data and provide evidence
• What is a directional hypothesis?

  It states the direction of the expected difference
• What is a non-directional hypothesis?

  It states there is a difference but not the direction
• When would a researcher use a directional hypothesis?

  If previous research indicates the expected direction
• What is the significance of the word "proof" in science?

  It implies absolute certainty, which is not possible
• What is falsifiability in science?

  A theory must be open to being proven false
• What probability threshold is used to accept the alternate hypothesis?

  One in 20 or less
• What does accepting the alternate hypothesis imply?

  The evidence is strong enough, but not perfect
• What should students avoid using in their essays regarding hypotheses?

  The word "prove"
• What are the types of hypotheses in research?

  • Null hypothesis (H0): No difference between conditions
  • Alternate hypothesis (H1): There is a difference
  • Directional hypothesis: Specifies the direction of the difference
  • Non-directional hypothesis: States there is a difference without direction