Unit 1 lesson 5
- 1. Unit 1: Background to Inferential Statistics Lesson 5: Measures of Distribution EDER 6010: Statistics for Educational Research Dr. J. Kyle Roberts University of North Texas Next Slide
- 2. Measures of Distribution Normal Distribution Characteristics: Mean = Median = Mode Skewness = 0 Kurtosis = 0 Next Slide 34.13% 34.13% 13.59% 13.59% 2.14% 2.14%
- 3. Skewness “Distributional Shape and the Blind Date” Sum of all of the Z-scores cubed Number of people in the study Skewness = 0, distribution is symmetrical < 0, negatively skewed > 0, positively skewed Next Slide
- 4. Skewness Next Slide Positively Skewed Negatively Skewed No Skewness
- 5. Many Forms of Skewness Next Slide
- 6. Kurtosis and the Blind Date Kurtosis is the ratio of height to width relative to the normal curve Next Slide Height Small Medium Large Men 5’9” 142-151 148-160 155-176 5’10” 144-154 151-163 158-180 5’11” 146-157 154-166 161-184 6’ 149-160 157-170 164-188 6’1” 152-164 160-174 168-192 6’2” 155-168 164-178 172-197 6’3” 158-172 167-182 176-202 Women 5’4” 114-127 124-138 134-151 5’5” 117-130 127-141 137-155 5’6” 120-133 130-144 140-159 5’7” 123-136 133-147 143-163 5’8” 126-139 136-150 146-167 5’9” 129-142 139-153 149-170 5’10” 132-145 142-156 152-173
- 7. Kurtosis Sum of all of the Z-scores to the fourth power Number of people in the study Next Slide
- 8. Kurtosis Next Slide Kurtosis = 0 Kurtosis > 0, Leptokurtic Kurtosis < 0, Platykurtic
- 9. Infinite Number of Normal Distributions Next Slide
- 10. Unit 1: Background to Inferential Statistics Lesson 5: Measures of Distribution EDER 6010: Statistics for Educational Research Dr. J. Kyle Roberts University of North Texas