As mentioned above, our approach is based on the fact that e-RA bids reveal some information about the suppliers' marginal costs (Zhang and Jin 2007), which may enhance the knowledge base of marginal costs beyond that introduced in previous research.
Many oil analysts include tax and revenue requirements in their estimate of marginal costs on the grounds that OPEC producers and other states need certain minimum prices and revenues to balance their budgets and avoid social unrest.
The review of empirical studies distinguishes between papers in which marginal costs are included in the observations and, hence, are directly used in the estimation and studies that treat marginal costs as a latent variable.
But the fact that Dupuit's prescription could result in the government having to recover for operational losses does not mean that Ekelund and Hebert are incorrect in arguing that Dupuit was not advocating marginal cost pricing where average cost is decreasing.
Overall, the marginal cost of the carbon storage activity ranges from $19 per metric ton ($17 per ton) from eliminating cotton production to $1,538 per metric ton ($1,395 per ton) for discontinuing soybean production on sandy soils.