I'm using timeOmics to model a time series of expression data on mRNA and proteins data. The amount of samples is rather small (7 groups, 2-7 samples per group) but the features space is rather large (8k in mRNA, 3k in proteins).
TimeOmics uses the lmms::lmmSpline algorithm for spline modeling and gives a option to choose between "cubic", "p-spline" or "cubic p-spline". I could not find any hard evidence on which splince would be best for my data and when I compared them, I just find that cubic p-splines receives more features as noise compare with the other models.
Would someone advise me on which spline would be best or recommend a paper where I could find that information?
Also, I am not sure if I should set the knots as the number of samples or leave it for the algorithm to decide.