Skip to main content
. Author manuscript; available in PMC: 2023 Sep 20.
Published in final edited form as: Stat Med. 2022 Jul 7;41(21):4266–4283. doi: 10.1002/sim.9505

FIGURE 2.

FIGURE 2

Basis functions for a single smoother for time. (A) Basis functions for a single smoother for time for the simulated data of Group 1 from this figure. (B) Matrix of basis function weights. Each basis function is multiplied by a coefficient which can be positive or negative. The coefficient determines the overall effect of each basis in the final smoother. (C) Weighted basis functions. Each of the four basis functions (and the intercept) of panel A has been weighted by the corresponding coefficient shown in Panel B. Note the corresponding increase (or decrease) in magnitude of each weighted basis function. (D) Smoother for time and original data points. The smoother (line) is the result of the sum of each weighted basis function at each time point, with simulated values for Group 1 shown as points