7.1.1.1 Directional and Non-Directional Hypotheses

• What is the purpose of a hypothesis in a study?

  To predict outcomes based on beliefs
• What is the role of a hypothesis in the scientific method?

  • Comes after initial observations
  • Precedes conducting experiments
  • Serves as a clear statement of expectations
• How does the "accept/reject hypothesis" step differ from the "draw conclusion" step in the scientific method?

  Accept/reject determines if the hypothesis is supported, while draw conclusion summarizes the overall findings
• What are the two main conditions for using a directional hypothesis?

  • Prior research suggests a specific direction of effect
  • Theoretical reasons support predicting a particular outcome
• How does a hypothesis relate to initial observations in research?

  A hypothesis is formed after making observations
• What are the key differences between directional and non-directional hypotheses?

  • Directional Hypothesis:
  • Specifies the direction of the effect (positive or negative)
  • Used when there is prior research supporting a specific direction
  • Non-Directional Hypothesis:
  • Does not specify the direction, only indicates an effect exists
  • Used when there is limited prior evidence or uncertainty about the direction
• When should a non-directional hypothesis be used?

  When prior research is limited or contradictory
• When should a directional hypothesis be used?

  When there is previous research supporting a specific direction
• What does a directional hypothesis predict?

  It predicts the specific direction of an effect
• What does a non-directional hypothesis indicate?

  It indicates a change without specifying direction
• When is a non-directional hypothesis more appropriate?

  When exploring a new area or contradictory research
• What are the key differences between one-tailed and two-tailed tests?

  • One-tailed tests:
  • Hypothesis is directional
  • Focuses on one side of the distribution
  • Two-tailed tests:
  • Hypothesis is non-directional
  • Considers both sides of the distribution
• What is the purpose of the scientific method?

  The scientific method is a systematic process to:

  • Investigate phenomena
  • Acquire new knowledge
  • Correct and integrate previous knowledge
• What are the two types of hypotheses in psychology?

  Directional and non-directional hypotheses
• How do directional and non-directional hypotheses differ in terms of research support?

  • Directional Hypotheses:
  • Require prior research or strong theoretical reasons
  • Non-Directional Hypotheses:
  • Suitable for new explorations or when evidence is contradictory
• What does an uncertain direction imply in a hypothesis?

  It indicates unsure if the effect will increase or decrease
• What are the steps of the scientific method?

  1. Make observations
  2. Construct hypothesis
  3. Test with experiment
  4. Draw conclusion
  5. Accept or reject hypothesis
  6. Report results
• What is the hypothesis type for two-tailed tests?

  Non-directional
• What is a hypothesis in the scientific method?

  A specific and testable prediction
• Why is a directional hypothesis used when there is prior research?

  Because existing studies support a specific direction
• Why is a non-directional hypothesis used when there is limited prior research?

  Because there isn't enough data to predict direction
• What does a non-directional hypothesis state?

  It states there will be a difference between conditions
• How does the scientific method help scientists make new discoveries?

  • Systematic process to test hypotheses
  • Allows for objective evaluation of ideas
  • Leads to new knowledge and understanding
  • Can be repeated to verify results
• What does a hypothesis indicate in research?

  What the researcher expects to find
• Why is the "test with experiment" step important in the scientific method?

  To gather data to evaluate the hypothesis
• What does it mean if previous studies have contradictory results?

  They disagree on the direction of the effect
• What is the first step of the scientific method?

  Make observations
• When is a directional hypothesis used?

  When there's a reason to predict an outcome's change
• What are the two types of tests in statistical testing?

  One-tailed and two-tailed tests
• Why is the hypothesis about flashcards considered directional?

  It specifically predicts an increase in performance
• What is a reason to use a directional hypothesis?

  Theoretical reasons justify predicting an outcome
• What does a two-tailed test consider?

  Both sides of the distribution
• What are the key features that differentiate directional and non-directional hypotheses?

  • Directional Hypothesis:
  • Specific prediction (increase or decrease)
  • Non-Directional Hypothesis:
  • General change without specifying direction
• What are the conditions for using a non-directional hypothesis?

  • Limited prior research
  • Contradictory results from previous studies
  • Uncertain direction of the effect
• If we hypothesize that a medication will affect test scores without specifying the direction, which test do we use?

  Two-tailed test
• What is the hypothesis type for one-tailed tests?

  Directional
• When do we choose a one-tailed test?

  When the hypothesis is directional
• If we expect a medication to increase test scores, which test do we use?

  One-tailed test