STATS 10 Lecture Notes - Lecture 4: Theoretical Definition, Standard Deviation
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Stats 10 lecture notes week 2 day 1. Big idea--your data set may have thousands of observations, Numeric summaries try to boil down the info into just a few values. W/ few summary values, we can make comparisons. Gpa--single value that summarizes academic performance (still doesn"t tell whole story) Suggestions for usage (just guidelines b/c the numeric summaries can be used for any set of data. If data is skewed, use median and iqr. B/c median and iqr are not affected by extreme values, mean and sd are affected by extreme values right- If data is symmetric, use mean and sd. B/c in symmetric data sets, the extremes balance each other out. Mean: x/n = 2+14+15+16 = 47/4 = 11. 75. Conceptual definition of mean: balance point of data. For skewed data, the mean of 11. 75 doesn"t tell whole story. 10 11 12 13 14 15 16 describes the center of the data.
