The slope b1 is computed by dividing the sum of the cross-products of deviations by the sum of the squared x-deviations. In the worked example, the sum of the cross-products is 6 and the sum of the squared x-deviations is 10, yielding b1=6/10=0.6.
Conditions: The data set consists of paired observations.; The sample means xˉ and yˉ have been computed.; The denominator ∑(xi−xˉ)2 is nonzero.
The slope b1 is computed by dividing the sum of the cross-products of deviations by the sum of the squared x-deviations. In the worked example, the sum of the cross-products is 6 and the sum of the squared x-deviations is 10, yielding b1=6/10=0.6.
Conditions: The data set consists of paired observations.; The sample means xˉ and yˉ have been computed.; The denominator ∑(xi−xˉ)2 is nonzero.
The y-deviations are calculated by subtracting the sample mean of the y-values, yˉ=4, from each individual y observation in the table. This produces a column of signed deviations measuring how far each point lies above or below the horizontal mean line.
Conditions: The y-values in the table are 2, 4, 5, 4, and 5.; The sample mean yˉ has been computed as 4.
The y-deviations are calculated by subtracting the sample mean of the y-values, yˉ=4, from each individual y observation in the table. This produces a column of signed deviations measuring how far each point lies above or below the horizontal mean line.
Conditions: The y-values in the table are 2, 4, 5, 4, and 5.; The sample mean yˉ has been computed as 4.