Exam 4: Numerical Descriptive Techniques

If the first and second quartiles are closer to each other than are the second and third quartiles, then the shape of the histogram based on the quartiles is ____________________.

Suppose that a firm's sales were $3,750,000 five years ago and are $5,250,000 today.What was the geometric mean growth rate in sales over the past five years?

What statistics and graphs can you use to look for a relationship between two interval variables?

Computers The following data represent the number of computers owned by a sample of 10 families from Chicago: 4, 2, 1, 1, 5, 3, 0, 1, 0, and 2. -{Computers Narrative} Compute the median number of computers.

If the distribution of a data set were perfectly symmetric, the distance from Q₁ to the median would always equal the distance from Q₃ to the median in a box plot.

Which of the following characteristics does a histogram help you identify?

Weights of Police Officers The following data represent the weights in pounds of a sample of 25 police officers: 164, 148, 137, 157, 173, 156, 177, 172, 169, 165, 145, 168, 163, 162, 174, 152, 156, 168, 154, 151, 174, 146, 134, 140, and 171. -{Weights of Police Officers Narrative} Calculate the 3rd and 7th deciles of the data.

A basketball player has the following points for seven games: 20, 25, 32, 18, 19, 22, and 30.Compute the following measures of central location: a. mean b. median c. mode

Quartiles divide the observations in a data set into four parts with the same amount of data in each part.

The interquartile range is an interval of numbers starting at Q₁ and ending at Q₃.

The shape of a distribution helps answer which question about the data?

Given the following sample data: a. Calculate the covariance and the correlation coefficient. b. Comment on the relationship between x and y. c. Determine the least squares line. d. Draw the scatter diagram and plot the least squares line.

Which of these measures of central location is not sensitive to extreme values?

In symmetric data, the value for Q₂ is always halfway between Q₁ and Q₃.

In the equation of the least squares line, , b₀ is the ____________________ and b₁ is the ____________________.

2-Year Investment Suppose you make a 2-year investment of $5,000 and it grows by 100% to $10,000 during the first year.During the second year, however, the investment suffers a 50% loss, from $10,000 back to $5,000. -{2-Year Investment Narrative} Compare the values of the arithmetic and geometric means.

The slope b₁ of the least squares line represents the:

The ____________________ of the correlation indicates the direction of a linear relationship.

Milk Demand A supermarket has determined that daily demand for milk containers has an approximate bell shaped distribution, with a mean of 55 containers and a standard deviation of six containers. -{Milk Demand Narrative} If the supermarket begins each morning with a supply of 67 containers of milk, how often will demand exceed the supply? (Give a percentage.)

Weights of Police Officers The following data represent the weights in pounds of a sample of 25 police officers: 164, 148, 137, 157, 173, 156, 177, 172, 169, 165, 145, 168, 163, 162, 174, 152, 156, 168, 154, 151, 174, 146, 134, 140, and 171. -{Weights of Police Officers Narrative} Determine the location and value of the 60th percentile of the weights.