Microsoft Office Tutorials and References

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**Syntax:**

Figure 14.21.

Figure 14.21.
As r-squared approaches 1.0, the predictive ability of the re-

As r-squared approaches 1.0, the predictive ability of the re-

gression line improves.

gression line improves.

•
The chart in the lower-left corner has an r-squared of 0.48. There

is a lot of variability in the dots, but they do seem to trend up. There

are huge relative errors on certain data points (for example, the

value of y equals 1 when x equals 7).

•
The chart in the upper-right corner shows a nearly perfect correl-

ation. The r-squared is appropriately high, at 0.988. This means that

most of the variability in y is explained by x. There are some tiny

minor variations above or below the line, but the regression is doing a

great job.

•
The final chart, in the lower right, illustrates a perfect correla-

tion and an r-squared of 1.0. Every occurrence of y falls exactly on

the regression line.