Top: permutation entropy per symbol and bottom: Jensen–Shannon complexity as a function of timescale τ for three embedded dimensions (d = 3, 4, and 5) calculated over 3-h intervals before the shock and in the sheath (covering almost the whole sheath). The solid thick lines show the results in the sheath, and the dashed lines show the results for the solar wind ahead. Bottom panels: the uncertainty ranges estimated using the permutation occupation number approach (see the text) are indicated as shaded areas for the sheath complexity curves. For d = 3, the errors are so small that the shaded area is not visible.