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Total Factor Productivity . Analytical Exercises. Simple vs. Compound Interest Rate. If you have a time deposit and receive a simple interest rate, then, after 1 year, your account will increase by the interest rate.
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Total Factor Productivity Analytical Exercises
Simple vs. Compound Interest Rate • If you have a time deposit and receive a simple interest rate, then, after 1 year, your account will increase by the interest rate. • If you receive a compound interest rate, rr(n), you may receive your extra income in increments which appear n times per year.
Define the compound interest rate with continuous compounding ρ = rr(n→∞), we calculate growth with the anti-log, e, • Refer to the log-difference as the continuous growth rate,
Natural Logarithmic Function • Natural Log Function has a number of useful (for the study of productivity) properties • Log of a Product is the sum of the logs • Log of exponent • Derivative of logarithm is the inverse
Growth Accounting • To study growth, take derivative of production function with respect to time. By the chain rule, Notation for CRTS implies βt = 1-αt, Price taking implies 1-αt is labor’s share of income.
Continuous Rate of Change • The time derivative of the logarithm of time dependent variable is the variables’ continuous rate of change. • Most economic series are observed only intermittently. We approximate the continuous rate of change with the first difference of the natural log:
Cobb-Douglas • Cobb-Douglas function is log-linear • Easy to do Growth Accounting because factor intensities are constant. TFP growth is proportional to technology growth.
TFP Growth • TFP is log linear
TFP growth rate is the gap between GDP growth rate and the weighted average of the growth rate of the factors of production.
Total Factor Productivity • Total factor productivity measures the total effectiveness of an economy in applying all of its factors of production. • TFP is a geometrically weighted average of capital and labor productivity with factor intensity, at and 1-at = used as weights.
Cobb-Douglas TFP • Since we can write • Under Cobb-Douglas, the level of TFP is a geometrically weighted function of capital productivity and labor productivity.
Growth Accounting Exercise: Celtic Tiger • Economy of Ireland has been one of the most successful in Europe in recent years transforming from one of the poorer countries of Europe to one of the richest over a period of about 25 years. • Growth accounting is a technique that economists use as a first step in explaining the sources of growth.
Growth Accounting • The growth accounting equation divides the sources of growth into 3 parts • Growth due to labor (i.e. growth in labor weighted by labor intensity, βt) • Growth due to capital (i.e. growth in capital weighted by capital intensity, αt) • Total Factor Productivity Growth (i.e. change in the production function itself).
Data • Question: What part of Irish growth is derived from labor growth, capital growth, or TFP growth? • Irish data is from " Marcel P. Timmer, Gerard Ypma and Bart van Ark (2003), IT in the European Union: Driving Productivity Divergence?, GGDC Research Memorandum GD-67 (October 2003), University of Groningen, Appendix Tables
Use approximation of growth accounting function • For every year, assume CRTS and write the approximate equation • Approximate labor intensity with the average of labor share of income in the previous year and the current year.
Growth Accounting Results • Growth Accounting suggests that approximately 30% of the growth in Irish GDP is due to growth in the capital stock about 10% is due to growth in the labor input and about 60% is due to TFP growth. • Of course, this brings up the question, why did TFP grow so much. • Note, we also did not adjust labor for quality improvements.
Cobb-Douglass • Easier to calculate if we assume constant TFP growth. Previous slide shows average (1-α) ≈2/3. Assume Cobb-Douglas production function and use this value. • Note average of ΔlnX from period 1 to T is So we only need to know start and stop values to calculate Growth Accounting. Results, not much different.
Item for DiscussionEast Asian Miracle • Another set of miracle economies over the last 30 years have been the economies of East and Southeast Asia. • What is the source of growth in these economies? • What are the implications for future growth.