những tác động của (và vấn đề vốn có trong) hội nhập thị trường vốn quốc tế, tăng trưởng, lạm phát và seignorage, chính sách uy tín, xác định thực tế và tỷ giá hối đoái danh nghĩa , và nhiều chủ đề đặc biệt thú vị chẳng hạn như các cuộc tấn công đầu cơ, | 229 Consumption Dynamics the Price Level and the Real Interest Rate not require the function c Ỉ2 Or CN to have the CES form we ve assumed any linear-homogeneous function will do. To recast the intertemporal problem we need only rewrite the lifetime budget constraint in terms of c. The obvious extension of the perfect-foresight constraint 60 of Chapter 2 derived in a single-good setting in section likewise forces the present value of consumption expenditure to equal the sum of financial and human wealth oo Ị s t 00 1 x5- 57 It. I CT S PsCti s 1 r Qt 57 TTT - Gs . 23 Here. G denotes total government spending on tradables and nontradables which is assumed to equal tax payments. Tradables are the numeraire in eq. 23 and the constant by assumption own-interest rate on tradables r must be used to discount future tradables flows. When written in terms of c using eqs. 14 and 21 eq. 23 boils down to 00 1 v 1 ụ r The consumer s intertemporal problem is to maximize eq. 19 with respect to Cj p subject to eq. 24 .27 The Real-Consumption Euler Equation and the Real Consumption-Based Interest Rate The consumer s financial asset-accumulation identity written as Qs Ỉ Qs rQs 3 WSLS Gs pscs can be used to substitute for cs in eq. 19 yielding 1 r Qi Qs i WSLS G ps Necessary conditions for intertemporal optimality come from differentiating with respect to gJTi r f. The resulting intertemporal Euler condition on total real consumption is wslsS Gs . 24 27. It is simplest to think of foreign assets as being indexed to tradables so that B bonds are a claim to rB tradables per period in perpetuity Different schemes for bond indexation yield identical results barring unanticipated shocks because under perfect foresight all assets must yield equal real returns however measured. We will use a slightly different scheme for indexing bonds in section . 230 The Real Exchange Rate and the Terms of Trade u Cs _ G 1 Cs1 0 1 An illuminating way to look at this last Euler
