Derivative estimation for longitudinal data analysis Articles uri icon

publication date

  • August 2018

start page

  • 2836

end page

  • 2854

issue

  • 37

volume

  • 37

international standard serial number (ISSN)

  • 0277-6715

electronic international standard serial number (EISSN)

  • 1097-0258

abstract

  • In a previous paper we derived equivalence relations for pseudo-Wronskian determinants of Hermite polynomials. In this paper we obtain the analogous result for Laguerre and Jacobi polynomials. The equivalence formulas are richer in this case since rational Darboux transformations can be defined for four families of seed functions, as opposed to only two families in the Hermite case. The pseudo-Wronskian determinants of Laguerre and Jacobi type will thus depend on two Maya diagrams, while Hermite pseudo-Wronskians depend on just one Maya diagram. We show that these equivalence relations can be interpreted as the general transcription of shape invariance and specific discrete symmetries acting on the parameters of the isotonic oscillator and Darboux-Poschl-Teller potential.

keywords

  • ALSPAC; derivative estimation; functional data analysis; longitudinal data analysis; penalized splines