After reading this chapter, you should be able to

• „„Explain the purpose of descriptive statistics.
   
• „„Distinguish between inferential and descriptive statistics.
   
• „„Explain the difference between a frequency distribution and a grouped frequency distribution.
   
• „„Read and interpret bar graphs, line graphs, and scatter plots.
   
• „„Calculate the mode, median, and mean.
   
• „„List the strengths and weaknesses of the mode, median, and mean.
   
• „„Explain positive skew and negative skew.
   
• „„Explain the impact of skewness on the measures of central tendency.
   
• „„Describe and interpret the different measures of variability.
   
• „„Calculate the range, variance, and standard deviation.
   
• „„Explain percentile ranks and z scores.
   
• „„Explain how to construct and interpret a contingency table.
   
• „„Explain the difference between simple and multiple regression.
   
• „„Explain the difference between the y-intercept and the regression coefficient.