Question

Problem 3) A recent study suggests that noise pollution can increase the risk of cardiovascular disease. This theory was investigated in a recent study where a random sample of adults who have lived in the same home for at least five years was obtained. The nighttime noise level (decibels) was measured in each home. Also, an index of cardiovascular risk was measured for each person; this index is called an Agatston score, determined with electron-beam computed tomography. An Agatson score indicates the level of coronary calcification: the higher the score, the greater the cardiovascular risk due to calcification of blood vessels.

a) What is the explanatory variable? The response variable? Use the Rossman/Chance applet Analyzing Two Quantitative Variables to make a scatterplot and find the least squares regression line for the relationship. Copy and paste the data including top row of Noise Agaston exactly as in the excel file, tab noise. Be careful assigning the explanatory and the response variable in the applet. You can toggle (Explanatory, Response) by clicking on it. Be sure that the applet designation is correct for your variables. You may need to toggle it. Print the screen with your scatterplot and analysis so we can refer to it in class. See the handout for what you need and the boxes to check.

b) Based on the scatterplot and correlation coefficient give the  Direction of relationship: Form: Strength of relationship:

In a table.

Noise level and cardiovascular risk

equation of least squares line in correct format

value for the correlation coefficient r

Interpretation of slope in the context of the problem Interpretation of y-intercept in the context of the problem

Predict the Agatston score for a person who lives in a home with a noise level of 45 decibels

Predict the Agatston score for a person who lives in a home with a noise level of 200 decibel

Answer 1

ANS::-

as for given data

A ) explanatory variable : Noise

B) Dependent variable : Agatston

By using excel we can calculate the scatter plot as

Put all the data in excel worksheet -----> click on Insert -------> Scatter plot -------> OK

Interpretation of scatterplot : There is positive linear relationship between noise and agatston.

B ) Direction of linear relationship : positive linear relationship

   Form : Linear

   Strength of linear relationship :

   By using the correlation coefficient we can measure the strength of linear relationship between two variables

By using excel we can compute the correlation coefficient by using the command

=CORREL(array1,array2)

we get r = 0.5650 > 0

I.e. There is moderate positively linear relationship between noise and agatston

THANK YOU.....!!!