Transit-timing residuals of WASP-19 b with respect to the best-fitting linear ephemeris. The red, blue, and purple points represent literature, Danish, and TESS data, respectively, with their associated timing uncertainties. The solid black, green, and brown curves correspond to the median fits from the linear, quadratic, and cubic polynomial models, respectively. Shaded regions indicate the 68 % confidence intervals derived from 20000 bootstrap realizations of each model’s MCMC posterior distribution.