Computing Regression using Excel

1

Make sure you have Data Analysis “Add-In”already in your Excel

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Select Regression

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Select the cells and tick the relevant boxes

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Summary output

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Getting your chart and Regression Line

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Double click on the chart and pull down the options for Charts- select the chart option with the ‘fx’

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You will then get your regression line with the regression equation too.

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Check that your regression variables match with the table that has been generated earlier (see slide 5)

Forecast

• Substitute the next period ( in this case Yr 9) into the equation and solve

• y = 1024.8x + 292.75• Solve for X=9

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What about MAD

• Go back to your regression generated table

• Look at the section on Residuals• List the values as absolute• Add and then divide by number of periods

to get average (MAD)

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Residuals

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Add the absolute values and divide by number of observations

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