Week 7 Assignment 1. Create a scatterplot to investigate the relation between a diamond’s weight and its price. Paste the scatterplot here. Ensure the axes are labeled, etc. 2. How would you describe...

Diamond assignment
1) We are to calculate the regression line between weight of diamond and price of diamond.
Scatter plot is as follows:
There seems to be approximately positive linear relationship between the two variables.
On X axis is plotted weight of diamond and on y axis the price of diamond
2) To find correlation coefficient:
Since correlation is positive, there is positive association. Also since 0.9447 is approximately nearer to 1, we get there is a strong linear positive
correlation between x and y.
3) A best fit line is one which has the sum of squares of deviations from observed the least. i.e. Observed – expected as per best fit line when squared and added should be the least. Such a line would be the line of best fit. This line passes through (xbar, y bar) always.
Suppose we have y =ax+b as the line of best fit then we must have
should be minimum
Using Calculus derivative test we obtain the formula for slope and intercept
Hence slope of the line and intercept are calculated using the formula shown below:
Regression line is
4) Yes. There is a causal relationship between price and weight. This is because correlation coefficient is 0.9447, very high.
5) Given that Several things besides smoking have been shown to be probabilistic causal factors in lung cancer—for example, exposure to asbestos and exposure to radon gas, both of which are found in many homes, can cause lung cancer. Suppose you meet a person who lives in a home that has a high radon level and insulation that contains asbestos. The person tells you, “I smoke, too, because I figure I’m doomed to cancer anyway.” What would you in response?
Smoking has a strong effect on getting lung cancer. Because already he is exposed to a high radon level and insulation, smoking will aggrate his chances of getting lung cancer. Hence his contention that I smoke, because I figure I’m doomed to cancer anyway cannot be accepted since smoking will increase the chances of early lung cancer. While precautions should be taken to avoid the bad effects of high radon and insulation, smoking should never be indulged into.
6) If given a chance to explore about correlation, I want to find out the correlation between hours of study and scores obtained,...