Exam 5: Numerical Descriptive Measures

The following data represent the ages (in years) of a sample of 25 employees from a government department: 31 43 56 23 49 42 33 61 44 28 48 38 44 35 40 64 52 42 47 39 53 27 36 35 20 Find the coefficient of variation.

The coefficient of determination lies between 0 and 1 (both inclusive).

A courier company is reviewing their delivery times. The following descriptive statistics relates to this courier company. The mean time for package delivery is 5 hours, the first quartile is 4 hours, the third quartile is 17 hours. This means that 75% of deliveries take more than 4 hours?

The frequency histogram for the heights (in cm) of the 25 students in a business statistics class is given below. What is the best measure of variability?

The following data represent the weights (in kilograms) of a sample of 30 horses: Weight 165 175 150 155 173 149 145 153 153 153 152 145 164 143 170 175 148 174 171 156 166 168 152 150 173 168 146 155 172 159 Compute the sample mean weight.

The coefficient of variation allows us to compare two sets of data based on different measurement units.

Which of the following would be the value of the correlation coefficient of two variables which are not linearly related.

Which of the following is not a measure of variability?

The coefficient of correlation is the covariance between the two variables divided by the standard deviations of the two variables.

The following data represent the ages (in years) of a sample of 25 employees from a government department: 31 43 56 23 49 42 33 61 44 28 48 38 44 35 40 64 52 42 47 39 53 27 36 35 20 Compute the range approximation to the standard deviation of the data. (Hint: S Range

Data were obtained for the weight in grams, of a sample of 10 packets of sweetener, as found in cafés. 4.5 5 5.9 5.4 5.5 4.7 4.9 4.7 4.7 4.6 Find the standard deviation.

The following data represent the numbers of bedrooms in a sample of 10 suburban houses in Mel-bourne: 3 3 2 2 4 5 2 5 4 2 Use these data to answer the following question/s. -Compute the coefficient of variation.

The following data represent the weights (in kilograms) of a sample of 30 horses: Weight 165 175 150 155 173 149 145 153 153 153 152 145 164 143 170 175 148 174 171 156 166 168 152 150 173 168 146 155 172 159 Determine the location and value of the lower quartile of the weights.

The annual percentage rates of return over the past 10 years for two mutual funds are as follows: Fund A: 7.1 -7.4 19.7 -3.9 32.4 41.7 23.2 4.0 1.9 29.3 Fund B: 10.8 -4.1 5.1 10.9 26.5 24.0 16.9 9.4 -2.6 10.1 Which fund would you classify as having the higher level of risk?

The following data represent the ages (in years) of a sample of 25 employees from a government department: 31 43 56 23 49 42 33 61 44 28 48 38 44 35 40 64 52 42 47 39 53 27 36 35 20 Construct a box plot for the age data and identify any outliers.

The difference between the largest and smallest values in an ordered array is called the range.

A sample of eight observations of variables x and y is shown below: x 5 3 7 9 2 4 6 8 y 20 23 15 11 27 21 17 14 Draw the scatter diagram and plot the least-squares line.

The following data represent the ages (in years) of a sample of 25 employees from a government department: 31 43 56 23 49 42 33 61 44 28 48 38 44 35 40 64 52 42 47 39 53 27 36 35 20 Compute the sample variance and sample standard deviation.

Which of the following is the best measure of variability if the distribution of a set of data is skewed?

The following data represent the salaries (in thousands of dollars) of a sample of 13 employees of a firm: 26.5 23.5 29.7 24.8 21.1 24.3 20.4 22.7 27.2 23.7 24.1 24.8 28.2 Compute the variance and standard deviation of the salaries.