HYPOTHESIS

• What is a hypothesis?

  A statement needing proof as true or false
• What are the types of hypotheses?

  • Null Hypothesis
  • Alternative Hypothesis (Research Hypothesis)
• What is the null hypothesis denoted by?

  H0
• What does the null hypothesis express?

  Non-significant difference
• How is the null hypothesis expressed?

  As an equality: 1st value = 2nd value
• What does the null hypothesis state about distributions?

  They are equal when compared
• What is the alternative hypothesis denoted by?

  Ha or H1
• What does the alternative hypothesis express?

  Significant difference
• How is the alternative hypothesis expressed?

  As an inequality using ≠, >, or <
• What does the alternative hypothesis state about distributions?

  They are not equal, greater, or less than
• What are the types of errors in hypothesis testing?

  • Type I (α – error)
  • Type II (β – error)
• What happens in a Type I error?

  Null hypothesis is rejected when true
• What happens in a Type II error?

  Null hypothesis is accepted when false
• What is the level of significance denoted by?

  Alpha, α
• What does the level of significance represent?

  Probability of committing a Type I error
• What does a level of significance of 0.05 mean?

  5% error tolerance in decision
• What confidence level corresponds to a 5% significance level?

  95% confidence level
• What determines the type of test to use in hypothesis testing?

  • Based on the alternative hypothesis
  • Types of tests:

  1. Two-tailed Test
  2. One-tailed Test
• What is a two-tailed test used for?

  To know if there is a difference
• How is a two-tailed test indicated?

  Using ≠ in the alternative hypothesis
• What is a one-tailed test used for?

  To know if one group is better or worse
• How is a one-tailed test indicated?

  Using < or > in the alternative hypothesis
• What is a one-tailed test with a negative critical value used for?

  To know if one group is worse
• How is a one-tailed test with a negative critical value indicated?

  Using < in the alternative hypothesis
• What is a one-tailed test with a positive critical value used for?

  To know if one group is better
• How is a one-tailed test with a positive critical value indicated?

  Using > in the alternative hypothesis
• What are common questions asked in research?

  1. Question of comparison
  2. Question of relationship significance
  3. Question of prediction
• What are the types of statistical tests for comparison?

  1. z-Test
  2. t-Test
  3. ANOVA
  4. F-Test
• What is the formula for the F-Test?

  F = bigger variance / smaller variance
• What tests are used for significance of relationship or association?

  • Pearson Product-Moment Correlation Coefficient
  • Spearman Rank-Order Correlation Coefficient
• What is used for forecasting or predicting?

  Linear Regression
• What are the steps in the hypothesis testing procedure?

  1. Formulate hypotheses
  2. Statistical test computation
  3. Decision making
  4. Conclusion
• What is the first step in hypothesis testing?

  Formulate the Null (H0) and Alternative (Ha) hypotheses
• What is the second step in hypothesis testing?

  Statistical test computation and summary of results
• What is the third step in hypothesis testing?

  Decision making based on critical value or p-value
• What is the fourth step in hypothesis testing?

  Answer the question posed in the problem
• What is the z-Test used for?

  To compare a group with the existing norm
• When can the z-Test be used?

  When population standard deviation, σ, is known
• What is the minimum sample size for using the z-Test?

  n ≥ 30
• What are the assumptions of the z-Test?

  1. Data is continuous
  2. Data is normally distributed
  3. Independence of observations
  4. Known population standard deviation
  5. Sufficiently large data size (n ≥ 30)