SOAN 2120 Lecture Notes - Lecture 4: Square Root, Standard Deviation, Statistical Significance

• School: University of Guelph
• Department: Sociology and Anthropology
• Course: SOAN 2120
• Professor: D Walters

Document Summary

For every observation: subtract observation from the mean, square that value. Divide that sum by the sample size minus 1. X = 8, 2, 3, 7, 4, 3. Calculate the mean: 8+2+3+7+4+3/6 = 27/6 = 4. 5. Sum up all the squared values: 12. 25 + 6. 25 + 2. 25 + 6. 25 + 0. 25 + 2. 25 = 29. 5. Divide that sum by the sample size minus 1: 29. 5/(n-1) = 29. 5/5 = 5. 9. Square root the answer: the square root of 5. 9 = 2. 429. X = 10, 2, 3, 7, 8, 9. Calculate the mean: 39/6 = 6. 5. Sum up all the squared values: 12. 25 + 20. 25 + 12. 25 + 0. 25 + 2. 25 + 6. 25 = 53. 5. Divide that sum by the sample size minus 1: 53. 5/5 = 10. 7. Square root the answer: the square root of 10. 7 is 3. 27. Every observation can be converted to a z-score. Z-scores can indicate whether an observation is statistically significantly different from the mean.