In the mathematical subfield of numerical analysis, an I-spline [1] [2] is a monotone spline function.
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In the mathematical subfield of numerical analysis, an I-spline [1] [2] is a monotone spline function.
A family of I-spline functions of degree k with n free parameters is defined in terms of the M-splines Mi(x|k, t)
where L is the lower limit of the domain of the splines.
Since M-splines are non-negative, I-splines are monotonically non-decreasing.
Let j be the index such that tj ≤ x < tj+1. Then Ii(x|k, t) is zero if i > j, and equals one if j − k + 1 > i. Otherwise,
I-splines can be used as basis splines for regression analysis and data transformation when monotonicity is desired (constraining the regression coefficients to be non-negative for a non-decreasing fit, and non-positive for a non-increasing fit).
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In the mathematical subfield of numerical analysis, an M-spline is a non-negative spline function.
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