Diagnosis
In linear regression, the value 0 is provided for an x value. It cannotbe determined at this point whether

• an incomplete data record x1, x2, ..... xn is involved that distorts
the result of the linear regression, or whether

• 0 represents a valid value for an x value.

Procedure
Check whether 0 is a valid value. If not, then the data records areincomplete. In this case, ensure that 0 values are excluded during dataretrieval for linear regression.