
Solow model with effective labour and government spending Consider a variant of the Solow model, where labour is measured in efficiency units and government spending, Gt?, is included on the assumption that government spending makes private capital (Kt?) and labour (Nt?) more productive. The technological progress variable, At?, in this model is called labour augmenting because it affects aggregate output by increasing the effectiveness of labour. The production function can be written in the following form: Yt?=Kt??(At?Nt?)?Gt?? where ?+?+?=1. Assume that the government runs a balanced budget, i.e. Gt?=?Yt? where ? is a tax rate on output. Consumers save a constant fraction s of disposable income. The rate of population growth is equal to n, and the depreciation rate equals d. (a) Derive the intensive form production function in terms of effective labour. [Hint: To derive intensive form production function, you divide both sides of the production function by At?Nt?. Use the relation 1??=?+? to substitute ?+? by 1??. In effective labour terms, balanced budget can be written as gt?=?yt?. From your function, how does the tax rate affect output? Q2.b (10 points) The capital stock, Kt?, evolves according to: Kt+1?=It?+(1?d)Kt? (b) Using the above law of motion, what is the steady-state condition for this economy? [Hint: Start by dividing both sides of the equation with At+1?Nt+1?. Note that the goods market is in equilibrium and that saving is s(1??)Yt?. Also, assume that At+1?Nt+1?=(1+n+z)At?Nt?, where z denotes a measure of labour productivity growth.] Q2.c (7 points) (c) Derive the steady-state level of capital per effective labour, k?, in terms of s,n,d,z, and ?. [Hint: Again, you need to use the relation 1??=?+? to substitute ?+? by 1?? when finding k?.] Q2.d (10 points) (d) Find the Golden Rule level of capital per effective worker, kG?. What is the saving rate that can help this economy to achieve kG? in the steady state? [Hint: Again, use the relation 1??=?+? to substitute ?+? by 1??.]