document.write( "Question 360393: Construct a scatterplot for the (x, y) values below, and answer the following questions. You do NOT need to submit your scatterplot with your answer; however, show all other work.
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document.write( "X   Y\r\n" );
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document.write( "1  -5\r\n" );
document.write( "2 -10\r\n" );
document.write( "3 =15\r\n" );
document.write( "4 -20\r\n" );
document.write( "5 -25\r\n" );
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Algebra.Com's Answer #257173 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
Construct a scatterplot for the (x, y) values below, and answer the following questions. You do NOT need to submit your scatterplot with your answer; however, show all other work.
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document.write( "X   Y\r\n" );
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document.write( "1  -5\r\n" );
document.write( "2 -10\r\n" );
document.write( "3 =15\r\n" );
document.write( "4 -20\r\n" );
document.write( "5 -25\r\n" );
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document.write( "Plot the five points\r\n" );
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document.write( "(1,-5), (2,-10), (3,-15), (4,-20), (5,-25)\r\n" );
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document.write( "Hmm!  This is different from most scatter plots because it is\r\n" );
document.write( "possible to draw a straght line through all 5 points.  Usually this\r\n" );
document.write( "is not possible and we have to find the line that comes the closest\r\n" );
document.write( "to fitting them all.  But this one is different, because they all\r\n" );
document.write( "lie on the same line, as you can see\r\n" );
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\n" ); document.write( "What would be the slope of this regression line?
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document.write( "Just pick any two of the points and use the slope formula.\r\n" );
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document.write( "Suppose we pick the points (2,-10) and (4,-20)\r\n" );
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document.write( "\"m\"\"%22%22=%22%22\"\"%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29\"\r\n" );
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document.write( "\"m\"\"%22%22=%22%22\"\"%28%28-20%29-%28-10%29%29%2F%28%284%29-%282%29%29\"\r\n" );
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document.write( "\"m\"\"%22%22=%22%22\"\"%28-20%2B10%29%2F%284-2%29\"\r\n" );
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document.write( "\"m\"\"%22%22=%22%22\"\"%28-10%29%2F2\"\r\n" );
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document.write( "\"m\"\"%22%22=%22%22\"\"-5\"\r\n" );
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\n" ); document.write( "Would the correlation between x and y be positive or negative?
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document.write( "It would be negative since the slope is negative.\r\n" );
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\n" ); document.write( "How would you interpret these data in terms of linear regression?
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document.write( "Since the regression line fits all the points perfectly, and the points\r\n" );
document.write( "move down to the right, the correlation coefficient is -1.\r\n" );
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document.write( "Edwin
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