Evaluating an Economic Forecast

An economist is building a model of a national economy. Which of the following relationships should be treated as a definitional identity, meaning it is true by definition and does not depend on the model's specific assumptions about economic behavior?

An economist analyzing a country's economy finds that the measured inflation rate is significantly different from the measured 'bargaining gap'. This empirical finding implies that the statement 'inflation is the percentage increase in prices' is an incorrect definition.

Analyzing an Economic Argument

An economist uses several mathematical relationships to describe an economy. Classify each of the following statements as either a 'Definitional Identity' (a statement that is true by definition) or a 'Model Prediction' (a statement that is only true under the specific assumptions of an economic model).

An economist builds a simple economic model based on the assumption that labor is the only cost of production. The model predicts that the inflation rate should be exactly equal to the percentage growth in wages. However, upon examining real-world data, the economist observes that the actual inflation rate is consistently different from the wage growth rate. What is the most logical conclusion to draw from this discrepancy?

Evaluating Economic Arguments

An economic model for a simplified, closed economy with no government sector predicts that National Savings = Investment. An analyst applies this model to a real-world open economy that includes government spending and international trade. They observe that the actual measured National Savings is not equal to the measured Investment. Which of the following statements best explains this discrepancy?

Constructing Economic Statements

An economic model makes a prediction that for a given country, aggregate consumption will be equal to 70% of national income. A researcher analyzing real-world data for that country finds that actual aggregate consumption was 65% of national income last year. The researcher concludes that the fundamental accounting identity, which states that total spending must equal total income, is therefore invalid. Which statement best identifies the flaw in the researcher's reasoning?