Psychology Week 4 Assignment: Correlation Application and Interpretation

Week 2 | Descriptive Statistics

Week 2 Assignment: Descriptive Statistics

Analysis based on the supplied Capella grades. JASP dataset (105 student records). Statistics and figures were calculated using Python as an alternative to JASP because of a software access issue. Confirm instructor approval for alternative output before submission.

Part 1: Final Exam Histograms

Lower division

This group includes 22 students. Final exam scores range from 48 to 72, with a mean of 62.45. The distribution has sample skewness of -0.30; the negative sign indicates a slight left skew. The histogram should also be inspected for clustering, gaps, and possible outliers.

Week 2 | Descriptive Statistics

Upper division

This group includes 83 students. Final exam scores range from 40 to 75, with a mean of 61.67. The distribution has sample skewness of -0.33; the negative sign indicates a slight left skew. The histogram should also be inspected for clustering, gaps, and possible outliers.

Part 2: Descriptive Statistics Variable N Mean SD Skewness Excess

kurtosis GPA 105 2.862 0.713 -0.220 -0.688 Quiz 3 105 7.133 1.600 -0.078 0.149 GPA: The mean is 2.862, and the standard deviation is 0.713. Skewness (-0.220) indicates a slight left skew. Excess kurtosis (-0.688) is below zero, suggesting a flatter/lighter-tailed distribution relative to a normal distribution. These measures alone do not establish normality.

Quiz 3: The mean is 7.133, and the standard deviation is 1.600. Skewness (-0.078) indicates a slight left skew. Excess kurtosis (0.149) is above zero, suggesting a more peaked/heavier-tailed distribution relative to a normal distribution. These measures alone do not establish normality.

Method note: Standard deviation uses the sample formula (n−1). Skewness and excess kurtosis use bias-corrected sample estimates. Different software settings can produce slightly different skewness/kurtosis values.