论坛里虽然有，但是好像不能下，这本书对于统计研究人员来说还是值得一读的。
SPLiNE FUNCTiONS: BASIC THEORY
LARRY L. SCHUMAKER
THIRD EDITION
CONTENTS
Preface xi
Preface to the 3rd Edition xv
Chapter 1 Introduction 1
1.1 Approximation Problems I
1.2 Polynomials 2
1.3 Piecewise Polynomials 3
1.4 Spline Functions 5
1.5 Function Classes and Computers 7
1.6 Historical Notes 9
Chapter 2 Preliminaries 12
2.1 Function Classes 12
2.2 Taylor Expansions and the Green's Function 14
2.3 Matrices and Determinants 19
2.4 Sign Changes and Zeros 24
2.5 Tchebycheff Systems 29
2.6 Weak Tchebycheff Systems 36
2.7 Divided Differences 45
2.8 Moduli of Smoothness 54
2.9 The K-Functional 59
2.10 n-Widths 70
2.11 Periodic Functions 75
2.12 Historical Notes 76
2.13 Remarks 79