STA 220 Lecture Notes - Lecture 4: Probability Plot, Histogram, Quartile
Document Summary
Sta 220 - lecture 4 - chapter 5. In comparing very different looking values - use standard deviations as our rulers. To tell us how the whole collection of values varies. It is the most common measure of deviation. Z = (y - ) / s . Formula for comparing individual data values to the mean, relative to their standard deviation. Resulting values standardized values denoted as z. Z-scores measure the distance of each data value from the mean in standard deviation. Negative z-score data value is below the mean. Positive z-score data value is above the mean. Small z-score value is close to the mean when compared to the rest of the data values. Large z-score value is far from the mean when compared to the rest of the data values. Standardized values have been converted from their original units to the standard statistical unit. Number of standard deviation away from the mean.
