Notice: This page requires JavaScript to function properly.
Please enable JavaScript in your browser settings or update your browser.
Impara Dynamic Regression and Distributed Lags | Time Series Analysis for Economics
R for Economists

bookDynamic Regression and Distributed Lags

Understanding how economic variables affect each other over time is crucial for policy analysis and forecasting. Often, the impact of a change in one variable, such as interest rates, is not immediate but unfolds over several periods. Distributed lag models are designed to capture these delayed or spread-out effects. In economic policy analysis, distributed lag models help you assess how shocks or policy interventions propagate through the economy. For example, a central bank's interest rate change may influence GDP growth not just in the current quarter but over several subsequent quarters. By explicitly modeling these lagged relationships, you can better understand both the timing and magnitude of economic responses, which is essential for effective policy design and evaluation.

12345678910111213141516171819202122232425262728293031323334
# Simulated quarterly time series data set.seed(123) gdp_growth <- ts(rnorm(100, 0.5, 1), start = c(2000, 1), frequency = 4) interest_rate <- ts(rnorm(100, 2, 0.5), start = c(2000, 1), frequency = 4) # Create lags of interest rate ir_lag0 <- interest_rate ir_lag1 <- stats::lag(interest_rate, -1) ir_lag2 <- stats::lag(interest_rate, -2) # Align series (remove NA caused by lags) data_aligned <- na.omit( ts.intersect( gdp_growth, ir_lag0, ir_lag1, ir_lag2 ) ) # Convert to data frame df <- as.data.frame(data_aligned) colnames(df) <- c( "gdp_growth", "ir_0", "ir_1", "ir_2" ) # Fit regression model <- lm(gdp_growth ~ ir_0 + ir_1 + ir_2, data = df) summary(model)
copy

Interpreting the coefficients in a dynamic regression model requires careful attention to the timing of effects. Each lagged coefficient quantifies the effect of the interest rate from a previous period on current GDP growth. For instance, the coefficient on the first lag shows how last quarter's interest rate influences this quarter's GDP. The sum of all lagged coefficients reveals the total effect distributed over time. Recognizing these dynamic effects is vital for economic policy: policymakers must anticipate not just the immediate impact but also the gradual adjustment of the economy. This perspective helps avoid over- or underestimating the consequences of policy changes and supports more informed, forward-looking decision-making.

question mark

What is the main advantage of using distributed lag models in economic policy analysis?

Select the correct answer

Tutto è chiaro?

Come possiamo migliorarlo?

Grazie per i tuoi commenti!

Sezione 3. Capitolo 3

Chieda ad AI

expand

Chieda ad AI

ChatGPT

Chieda pure quello che desidera o provi una delle domande suggerite per iniziare la nostra conversazione

Suggested prompts:

Can you explain how to interpret the regression output in more detail?

What does it mean if the lagged coefficients are not statistically significant?

How can I modify the model to include more lags or other variables?

bookDynamic Regression and Distributed Lags

Scorri per mostrare il menu

Understanding how economic variables affect each other over time is crucial for policy analysis and forecasting. Often, the impact of a change in one variable, such as interest rates, is not immediate but unfolds over several periods. Distributed lag models are designed to capture these delayed or spread-out effects. In economic policy analysis, distributed lag models help you assess how shocks or policy interventions propagate through the economy. For example, a central bank's interest rate change may influence GDP growth not just in the current quarter but over several subsequent quarters. By explicitly modeling these lagged relationships, you can better understand both the timing and magnitude of economic responses, which is essential for effective policy design and evaluation.

12345678910111213141516171819202122232425262728293031323334
# Simulated quarterly time series data set.seed(123) gdp_growth <- ts(rnorm(100, 0.5, 1), start = c(2000, 1), frequency = 4) interest_rate <- ts(rnorm(100, 2, 0.5), start = c(2000, 1), frequency = 4) # Create lags of interest rate ir_lag0 <- interest_rate ir_lag1 <- stats::lag(interest_rate, -1) ir_lag2 <- stats::lag(interest_rate, -2) # Align series (remove NA caused by lags) data_aligned <- na.omit( ts.intersect( gdp_growth, ir_lag0, ir_lag1, ir_lag2 ) ) # Convert to data frame df <- as.data.frame(data_aligned) colnames(df) <- c( "gdp_growth", "ir_0", "ir_1", "ir_2" ) # Fit regression model <- lm(gdp_growth ~ ir_0 + ir_1 + ir_2, data = df) summary(model)
copy

Interpreting the coefficients in a dynamic regression model requires careful attention to the timing of effects. Each lagged coefficient quantifies the effect of the interest rate from a previous period on current GDP growth. For instance, the coefficient on the first lag shows how last quarter's interest rate influences this quarter's GDP. The sum of all lagged coefficients reveals the total effect distributed over time. Recognizing these dynamic effects is vital for economic policy: policymakers must anticipate not just the immediate impact but also the gradual adjustment of the economy. This perspective helps avoid over- or underestimating the consequences of policy changes and supports more informed, forward-looking decision-making.

question mark

What is the main advantage of using distributed lag models in economic policy analysis?

Select the correct answer

Tutto è chiaro?

Come possiamo migliorarlo?

Grazie per i tuoi commenti!

Sezione 3. Capitolo 3
some-alt