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Identify each of the following variables as either categorical or quantitative. a. Choice of diet (vegan, vegetarian, neither) b. Time spent shopping online per week c. Ownership of a tablet (yes, no) d. Number of siblings

Student scores A student wants to examine the distribution of his scores as shown on his academic transcript. To this end, he constructs the stem-and-leaf plot of his records: $$ \begin{array}{l|l} 6 & 588 \\ 7 & 01136779 \\ 8 & 1223334677789 \\ 9 & 011234458 \end{array} $$ a. Identify the number of courses validated by the student, his minimum and maximum scores. b. Sketch a dot plot for this data. c. Sketch a histogram for this data with intervals of length 10 .

Consider the following three sets of observations: Set 1: 8,9,10,11,12 Set 2: 8,9,10,11,100 Set 3: 8,9,10,11,1000 a. Find the median for each data set. b. Find the mean for each data set. c. What do these data sets illustrate about the resistance of the median and mean?

The workers and the management of a company are having a labor dispute. Explain why the workers might use the median income of all the employees to justify a raise but management might use the mean income to argue that a raise is not needed.

According to the National Association of Home Builders, the median selling price of new homes in the United States in February 2014 was \(\$ 261,400\). Which of the following is the most plausible value for the standard deviation: \(-\$ 15,000, \$ 1000, \$ 60,000,\) or \(\$ 1,000,000 ?\) Why? Explain what's unrealistic about each of the other values.

If the largest observation is less than 1 standard deviation above the mean, then the distribution tends to be skewed to the left. If the smallest observation is less than 1 standard deviation below the mean, then the distribution tends to be skewed to the right. A professor examined the results of the first exam given in her statistics class. The scores were $$\begin{array}{llllllll} 35 & 59 & 70 & 73 & 75 & 81 & 84 & 86 \end{array}$$ The mean and standard deviation are 70.4 and 16.7 . Using these, determine whether the distribution is either left or right skewed. Construct a dot plot to check.

Continuous or discrete? Which of the following variables are continuous, when the measurements are as precise as possible? a. Age of mother b. Number of children in a family c. Cooking time for preparing dinner d. Latitude and longitude of a city e. Population size of a city

According to a recent report from the U.S. National Center for Health Statistics, females between 25 and 34 years of age have a bell-shaped distribution for height, with mean of 65 inches and standard deviation of 3.5 inches. a. Give an interval within which about \(95 \%\) of the heights fall. b. What is the height for a female who is 3 standard deviations below the mean? Would this be a rather unusual height? Why?

The data values below represent the closing prices of the 20 most actively traded stocks on the NASDAQ Stock Exchange (rounded to the nearest dollar) on May \(2,2014 .\) \(\begin{array}{cccccccccc}3 & 60 & 40 & 87 & 26 & 9 & 37 & 23 & 26 & 9 \\ 4 & 78 & 4 & 7 & 26 & 7 & 52 & 8 & 52 & 13\end{array}\) a. Sketch a dot plot or construct a stem-and-leaf plot. b. Find the median, the first quartile, and the third quartile. c. Sketch a box plot. What feature of the distribution displayed in the plot in part a is not obvious in the box plot? (Hint: Are there any gaps in the data?)

The mean GPA for all students at a community college in the fall semester was 2.77. A student with a GPA of 2.0 wants to know her relative standing in relation to the mean GPA. A numerical summary that would be useful for this purpose is the a. standard deviation b. median c. interquartile range d. number of students at the community college