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The NLIN Procedure |

**BOUNDS***inequality < , ... , inequality >***;**

The BOUNDS statement restrains the parameter estimates within specified bounds. In each BOUNDS statement, you can specify a series of bounds separated by commas. The series of bounds is applied simultaneously. Each bound contains a list of parameters, an inequality comparison operator, and a value. In a single-bounded expression, these three elements follow one another in the order described. The following are examples of valid single-bounded expressions:

bounds a1-a10<=20; bounds c>30; bounds a b c > 0;

Multiple-bounded expressions are also permitted. For example,

bounds 0<=B<=10; bounds 15<x1<=30; bounds r <= s <= p < q;

If you need to restrict an expression involving several
parameters (for example, *A*+*B*<1), you can reparameterize
the model so that the expression becomes a parameter.

For SAS versions 7.01 and later,
lagrange multipliers are reported for all bounds that
are enforced (active) when the estimation terminates. In the estimates
table and in the OUTEST= data set, the Lagrange multiplier estimates
are identified with names *Bound1*, *Bound2* ... .
An active bound is treated as if a restriction was applied to
the set of parameters so one parameter degree of freedom is deducted. The
option NOCORRECTEDDF specifies that no degrees of freedom are lost
when a bound is active.
Lagrange multiplier based bounds are not used for METHOD=DUD.

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