Causes of the European debt crisis historian Robert Skidelsky added that it was indeed excessive lending by banks, not deficit spending that created this crisis. Government's mounting debts are a response to the economic downturn as spending rises and tax revenues fall, not its cause. Either way, high debt levels alone may not explain the crisis. According to The Economist Intelligence Unit, the position of the euro area looked "no worse and in some respects, rather better than that of the US or the UK." The budget deficit for the euro area as a whole (see graph) is much lower and the euro area's government debt/GDP
Optimal foraging theory items that an animal should carry back to its nesting site or the optimal size of a food item that an animal should feed on. Figure 1, shows an example of how an optimal decision rule could be determined from a graphical model. The curve represents the energy gain per cost (E) for adopting foraging strategy x. Energy gain per cost is the currency being optimized. The constraints of the system determine the shape of this curve. The optimal decision rule (x*) is the strategy for which the currency, energy gain per costs, is the greatest. Optimal foraging models can