Class01_W2 - Chapter2 STAT 606 Graphical methods may not always be sufficient for describing data Numerical measures can be created for both populations

Class01_W2 - Chapter2 STAT 606 Graphical methods may not...

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  STAT 606Chapter 2Descriptive Statistics
Describing Data with Numerical MeasuresGraphical methods may not always be sufficient for describing data.Numerical measures can be created for both populations populations and samples.samples.A parameter parameter is a numerical descriptive measure calculated for a populationpopulation.A statistic statistic is a numerical descriptive measure calculated for a samplesample.
Describing Central TendencyA measure along the horizontal axis of the data distribution that locates the center center of the distribution.
Three measuresArithmetic MeanMedianMode
Arithmetic Mean or AverageThe mean mean of a set of measurements is the sum of the measurements divided by the total number of measurements.nxxi=where n = number of measurementstsmeasurementheallofsum=ix
ExampleThe set: 2, 9, 1, 5, 6==nxxi6.65335651192==++++If we were able to enumerate the whole population, the population meanpopulation meanwould be called μμ(the Greek letter “mu”).
The median median of a set of measurements is the middle measurement when the

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