Test 10 Statistics

Question: B. Using the linear correlation coefficient found in the previous​ step, determine whether there is sufficient evidence to support the claim of a linear correlation between the two variables. Choose the correct answer below. C. Identify the feature of the data that would be missed if part​ (b) was completed without constructing the scatterplot. Choose the correct answer below.

Answer: B. There is sufficient evidence to support the claim of a linear correlation between the two variables. C. The scatterplot reveals a distinct pattern that is not a​ straight-line pattern.

Question: B. Using the linear correlation coefficient found in the previous​ step, determine whether there is sufficient evidence to support the claim of a linear correlation between the two variables. Choose the correct answer below. C.Identify the feature of the data that would be missed if part​ (b) was completed without constructing the scatterplot. Choose the correct answer below.

Answer: B.There is sufficient evidence to support the claim of a linear correlation between the two variables. C.The scatterplot reveals a perfect​ straight-line pattern, except for the presence of one outlier.

Question: A. Do the data points appear to have a strong linear​ correlation? B.Is there a linear correlation between x and​ y? Use α= 0.01. C.Is there a linear correlation between x and​ y? Use α​= 0.01. D.What do you conclude about the possible effect from a single pair of​ values?

Answer: A. Yes. B.Yes​, because the correlation coefficient is in the critical region. C.No​,because the correlation coefficient is not in the critical region. D.The effect from a single pair of values can change the conclusion.

residual plot

Is a scatterplot of the​ (x,y) values after each of the​ y-coordinate values has been replaced by the residual value y−y.

If we find that there is a linear correlation between the concentration of carbon dioxide in our atmosphere and the global​ temperature, does that indicate that changes in the concentration of carbon dioxide cause changes in the global​ temperature?

No. The presence of a linear correlation between two variables does not imply that one of the variables is the cause of the other variable.

influential points

Paired sample data may include one or more______which are points that strongly affect the graph of the regression line.

What is the difference between the following two regression​ equations?

The first equation is for sample​ data; the second equation is for a population.

In what sense is the regression line the straight line that​ "best" fits the points in a​ scatterplot?

The regression line has the property that the -sum of squares-of the residuals is the -lowest- possible sum.

Which of the following statements about correlation is​ true?

We say that there is a positive correlation between x and y if the​ x-values increase as the corresponding​ y-values increase.

scatterplot

When determining whether there is a correlation between two​ variables, one should use a____to explore the data visually.

linear correlation coefficient r

measures the strength of the linear correlation between the paired quantitative​ x- and​ y-values in a sample.

What is a​ residual?

A residual is a value of y−y​, which is the difference between an observed value of y and a predicted value of y.

Which of the following is not equivalent to the other​ three?

Dependent variable

residual

For a pair of sample​ x- and​ y-values, the​ ______________ is the difference between the observed sample value of y and the​ y-value that is predicted by using the regression equation.

regression equation

Given a collection of paired sample​ data, the____ y=b0+b1x algebraically describes the relationship between the two​ variables, x and y.

correlation

exists between two variables when the values of one variable are somehow associated with the values of the other variable.

outlier

is a point lying far away from the other data points.