M03-Activity

STAT-S301 · Applied Statistical Methods for Business · Summer 2023 In-Class Activity M03 Name Group Members 1) 2) 3) 4) 1974 MotorTrend Magazine Dataset Go to Canvas Modules M03 M03 In-Class Activity and download the Excel dataset: mtcars.xlsx . The data was taken from a 1974 issue of the American magazine MotorTrend . It contains 12 variables on 32 different types of vehicles, but for this activity we’ll only be using mpg and wt , the miles per US gallon and the weight (1000lbs), respectively. 1 Z-Scores What is more unusual? A car that weighs more than 5K lbs (5000 lbs) or a car that gets better than 30 miles per gallon? This is a difficult question to answer because we are trying to compare two variables with different units/scales. A way to get around these issues is to compare both on a standardized scale. The most common way of standardizing a value is through the Z-score: Z = x − µ σ or Z = x − ¯ x s ( µ is the known mean; ¯ x is the mean estimated from data. σ is a known standard deviation; s is the standard deviation estimated from data.) Round your answers to two decimal places for the questions below. The mean wt of the 32 cars is , and the standard deviation of wt is . The mean mpg of the 32 cars is , and the standard deviation of mpg is . Now, if a vehicle is 5000 pounds (5K lbs) and gets 30 miles per gallon, The z-score for the weight would be . The z-score for the miles per gallon would be . Therefore, between the wt and mpg , the value that makes this car more unusual is the . 20.09 6.03 3.22 0.98 wt 1.82 1.64 Jackson Dumas Jackson Dumas No Group Assigned