Exam 6: Exploring Data: Relationships

A bank collects data on the savings and incomes of families to predict an expected increase in certificate of deposit accounts due to a 10% increase in salaries of employees at a local company. Which variable, savings or income, would be the explanatory variable?

Use the following scatterplot to answer the Questions: -What can you say about the association of the variables?

Use the following scatterplot to answer the Questions: -For the scatterplot shown above, what y value would you expect to be paired with x = 9?

If the regression line is $y$ = 0.01 $x$ + 3.14, which of the following must hold true?

Use the table below to answer the following Questions . Temperature in degrees F(y) 70 72 74 75 81 82 83 84 89 93 Chirps per second (x) 15 15 15 16 17 17 16 17 19 20 -Let x = number of chirps per second and y = temperature. What is the slope of the regression line?

When the units of measurement are changed, what happens to the correlation of the data?

What is the correlation?

Suppose the children of a primary school are surveyed. What type of association would you expect between their ages and their height?

An airline has determined that the relationship between the number of passengers (x) on a flight and the total weight (y) (in pounds) of luggage stored in the baggage compartment can be estimated by the least-squares regression equation y = 250 + 27x. Predict the weight of luggage for a flight with 125 passengers.

When the units of measurement are changed, what will happen to the least-squares regression line?

If the least-squares regression line is $y = - 2 x + 17$ then what is the residual for the point (7, 5)?

A shopping mall is having trouble with shoplifting in several of its stores. For the variables representing the number of security guards on patrol and the number of shoplifting incidents, you would expect: A)a substantial negative correlation. B)a substantial positive correlation. C)a small correlation. D)no correlation.

Use the following scatterplot to answer the Questions: -For the scatterplot shown above, what can you say about the least-squares regression line?

If the correlation between x and y is 0, this means that:

Each additional hour of studying adds, on average, how many test points?

The intercept of the least-squares regression line is:

Suppose the equation for a regression line has a positive slope. What type of association exists between the variables?

Suppose the babies in a nursery are surveyed. What type of association would you expect between a child's age and the average number of hours the child sleeps in a day?

An outlier is an individual value that:

Use the following data to answer the Questions: 66 118 50 99 73 120 69 121 72 123 65 108 62 111 -Make a scatterplot of the data.