“…In other words, our model nests various existing proposals in the literature, offering a unified discrete-time framework that we investigate in detail. Other related work on optimal order execution with (exponentially) decaying (linear) transient price impact in discrete and continuous time include, e.g., Alfonsi et al [5], Alfonsi and Schied [8], Predoiu et al [49], Alfonsi et al [9], Gatheral et al [31], Lorenz and Schied [45], Alfonsi and Schied [7], Alfonsi and Acevedo [3], Bank and Fruth [17], Alfonsi and Blanc [4], Fruth et al [28,29], Graewe and Horst [33], Lehalle and Neuman [43], Horst and Xia [37], Chen et al [24], Ackermann et al [1,2], Forde et al [27], Neuman and Voß [46]. Moreover, in the linear case, we also establish a new explicit formula, see Proposition 1, for the optimal execution strategy with stochastic transient price impact and inventory penalty, which extends the explicit deterministic solution from Obizhaeva and Wang [47] and allows us to also accurately benchmark our machine learning approach.…”