Descriptive Stats

• What was the focus of the researchers' study?

  Therapies for stress
• How were participants assessed in the study?

  Using a standardized test of mood
• What did a low score indicate in the mood assessment?

  Negative mood
• What was the range of mood scores in the study?

  24 to 83
• What was the mean mood score for Group 1?

  36.4
• What was the mean mood score for Group 2?

  60.5
• Why were the mood scores assumed to be interval data?

  Because the test of mood was standardized
• How can mood scores be converted to ordinal data?

  • Order all mood scores from lowest to highest
  • Assign ranks to each score
  • Equal scores share the same rank
• How can mood scores be converted to nominal data?

  • Categorize scores into groups based on mood
  • Example categories:
  • Scores under 40
  • Scores between 40 and 60
  • Scores over 60
• What are measures of central tendency?

  Values that represent the center of data
• What is the mean?

  The mathematical average of data points
• When is the mean most appropriate to use?

  For interval data without outliers
• What is a key evaluation point of the mean?

  It is sensitive to all scores in data
• What is the median?

  The midpoint value of ordered data
• How do you find the median?

  Order data and find the middle value
• When can the median be used?

  For interval and ordinal data, including outliers
• What is a key evaluation point of the median?

  It is not affected by outliers
• What is the mode?

  The most common data point
• When can the mode be used?

  For interval, ordinal, and nominal data
• What is a key evaluation point of the mode?

  It can be crude and not represent all data
• What is the range in descriptive statistics?

  The difference between highest and lowest values
• What is a key evaluation point of the range?

  Easy to calculate but affected by extremes
• What is the standard deviation?

  Average distance of data points from the mean
• What is a key evaluation point of the standard deviation?

  Precise but may hide extreme values
• What are the differences between traditional CBT and brief CBT?

  • Traditional CBT is marginally more effective
  • Not enough difference to claim significant effectiveness
  • Brief CBT shows more variation in effectiveness
  • Traditional CBT likely works similarly for all patients
• What is the maximum score for the mock exam mentioned?

  72
• Why is the median the most appropriate measure for the mock exam scores?

  Due to the extreme score of 72
• What was the median score for the mock exam results?

  5.5
• Why is the mode inappropriate for the mock exam scores?

  No two students had the same score
• Why is the mean inappropriate for the mock exam scores?

  There is an extreme score of 72
• What is the purpose of descriptive statistics?

  To summarize and describe data
• What do descriptive statistics not allow us to do?

  Infer conclusions about hypotheses
• What is the significance of positive, negative, and zero correlations?

  They describe relationships between variables
• What is the main focus of measures of dispersion?

  To inform about the spread of data
• What does a higher number in measures of dispersion indicate?

  More variation among participants
• What is the simplest measure of dispersion?

  The range
• How is the range calculated?

  Subtract the lowest value from the highest
• What is a key evaluation point of the range?

  Very affected by extreme values
• What does the standard deviation measure?

  Average distance from the mean
• Why is the standard deviation considered precise?

  It accounts for all exact values