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Using the second-order Taylor expansion of the Lagrangian from the Ramsey optimal savings model, wealth is included in the quadratic loss function, and not only consumption. The weight assigned to wealth is determined by the degree of concavity of the decreasing returns to scale production function multiplied by the marginal utility of consumption, whereas the weight assigned to consumption is determined by the degree of concavity of the utility function. This quadratic loss function implies that the speed of convergence is explicitly driven by the trade-off between wealth smoothing (fostering convergence, related to technology) and consumption smoothing (delaying convergence, related to preferences). By contrast, the second-order Taylor expansion of the utility (instead of the Lagrangian) leads to a quadratic loss function with a weight of wealth equal to zero, which is false for a decreasing returns to scale production function.