Histograms show continuity of data i.e. continuous interval. Enough intervals will produce a smooth graphic. Measures of Variability Range Range is Y max Y min . This relationship is also determined by boxplots. Deviation Difference of each score from the mean.
Deviation always sums to zero.
Sum of Squares Variance Standard Deviation Normal Distribution Standard Normal Distribution Symmetric bell-shaped, but with the property that one unit equals one standard deviation. Sampling Distribution Determines the likelihood of obtaining a statistic of a given value. This assumes an infinite number of samples. Where is the mean of all sample means from the infinite number of samples and is the population mean of the population sampled. Each mean attempts to approximate the population mean.