AbstractWe prove that various Durrmeyer-type operators preserve q-monotonicity in [0, 1] or $$[0,\infty )$$
[
0
,
∞
)
as the case may be. Recall that a 1-monotone function is nondecreasing, a 2-monotone one is convex, and for $$q>2$$
q
>
2
, a q-monotone function possesses a convex $$(q-2)$$
(
q
-
2
)
nd derivative in the interior of the interval. The operators are the Durrmeyer versions of Bernstein (including genuine Bernstein–Durrmeyer), Szász and Baskakov operators. As a byproduct we have a new type of characterization of continuous q-monotone functions by the behavior of the integrals of the function with respect to measures that are related to the fundamental polynomials of the operators.