Welham, S.J.; Thompson, R. - In: Computational Statistics & Data Analysis 53 (2009) 4, pp. 920-931
For a smoothing spline or general penalized spline model, the smoothing parameter can be estimated using residual maximum likelihood (REML) methods by expressing the spline in the form of a mixed model. The possibility of bimodality in the profile log-likelihood function for the smoothing...