# Chapter 3

 Measure of center the value at the center or middle data set E sum of a set of values x the variable for individual data values n number of data values in a sample N represents the number of data values in a population bimodal two modes multimodal more than two modes midrange maximum value + minimum value____________________________                      2 decimal point rule for measures of center carry one more decimal place than is present in the original set of values Measures of center mean medianmodemidrange variance is s2 standard diviation squared Range rule of thumb Minimum "usual" value = (mean) - 2 x (standard deviation) Maximum "usual" value = (mean) + 2 x (standard deviation) Range rule of thumb for estimating a value of the standard deviation s To roughly estimate the standard deviation from a collection of known sample data use To roughly estimate the standard deviation from a collection of known sample data use  s = range     -------        4 Empirical rule For bell shaped distributions68-95-99.7 Chebyshev's Theorem 1-1/k2 CV cv= s    X 100%     ---     __      X z score is rounded to 2 decimal places z score z= x- mean devided by s percintile of value x percentile of value x= number of values less than x devided by total number of values multiplied by 100 Converting from the kth percentile to the corresponding data value Locator = K (percentile being used) devided by 100 multiplied by n (total number of values in the data set) Authorservinggod247 ID276281 Card SetChapter 3 Descriptiontest one Updated2014-06-06T21:00:16Z Show Answers