TREASURY has admitted that an analysis in last month's budget exaggerated the positive effect of government stimulus measures on economic growth in countries around the world.

Treasury said its decision to include only the favourable findings from its study of the impact of fiscal stimulus programs in G20 countries was an error, rather than a selective use of statistics.

And, in a statement to Senate estimates, executive director of Treasury's macroeconomic group David Gruen insisted there was still strong evidence that stimulus measures had boosted growth in industrial economies, despite the flaw in the G20 analysis.

Outraged RMIT University economics professor Sinclair Davidson accused Treasury of ''data snooping'' - using only data that fits a hypothesis rather than using all relevant data to test a view.

The department's analysis in the budget concluded that countries like Australia, which adopted large and prompt stimulus policies in response to the global financial crisis, had performed better than countries with smaller stimulus programs.