2017年-世界发展银行全球_Applying_Behavioral_Insights_to_Improve_Tax_Collection___Experimental_Evidence_from_Poland_68页_6mb

Summary of "Applying Behavioral Insights to Improve Tax Collection: Experimental Evidence from Poland"

Core Content

This report presents the findings of a randomized controlled trial (RCT) conducted in Poland to evaluate the impact of behavioral insights on tax compliance. The experiment tested different types of messages and delivery methods in letters sent to taxpayers who had declared their personal income tax (PIT) for 2015 but had not paid by the April 30, 2016 deadline.

Main Objectives

1. To assess the effect of different behavioral messages on tax compliance.
2. To determine if the delivery method (registered vs. regular mail) influenced tax compliance outcomes.

Key Findings

Message 1: Behavioral letters significantly improved tax compliance compared to dunning letters

• Payment rate: 40.2% for dunning letters vs. 42.9–48.6% for behavioral letters.
• Most effective letter: Combined deterrence and omission messages, increasing the payment rate by 8.4 percentage points (pp) and payment amount by PLN 347.
• Least effective letter: Public goods message, which increased the payment rate by 6.7%.
• Standard behavioral letter: Achieved a 46.3% payment rate, 6.1 pp higher than the dunning letter, representing a 15.2% increase in compliant taxpayers.

Message 2: 'Hard-tone' messages were more effective than 'soft-tone' messages

• Hard-tone messages: Highlighted sanctions or framed nonpayment as a deliberate choice, leading to higher payment rates and amounts.
• Soft-tone messages: Focused on social incentives or public goods, with less impact.
• Payment rate: 46.9% for hard-tone vs. 43.9% for soft-tone.
• Payment amount: Hard-tone messages mobilized an average of PLN 93 more than soft-tone messages.

Message 3: Message effectiveness varied by taxpayer characteristics

• Age: Public goods messages were effective for younger taxpayers (20–29), but had a negative effect on those aged 50–64.
• Location: Public goods messages were more effective in rural areas.
• Tax liability: Some messages were more effective for taxpayers with higher liabilities.

Message 4: Regular mail was as effective as registered mail

• Payment rates and amounts: No statistically significant difference between delivery methods.
• Cost savings: Using regular mail (PLN 9.20 per letter) instead of registered mail (PLN 14.96 per letter) could save the tax authority money without compromising compliance.

Message 5: Behavioral interventions are cost-effective

• Cost-benefit analysis: Sending the most effective letter to all 149,925 taxpayers would generate an additional PLN 39,328,742 in revenue.
• Cost: The cost of sending the letters was minimal compared to the revenue generated (28 times more revenue than cost).
• Conclusion: Behavioral insights can be used to enhance tax compliance at low cost, without the need for new legislation.

Experimental Design

• Sample size: 149,925 taxpayers in arrears.
• Trial period: May to August 2016.
• Control group: Received the standard dunning letter via regular mail.
• Treatments: Nine behavioral letters with different messages (e.g., deterrence, social norms, public goods, self-image, reciprocity).
• Outcomes measured:
  • Payment rate (binary)
  • Payment amount (continuous)
  • Outstanding tax liability (continuous)

Methodology

• Randomization: Stratified to ensure balance across treatment groups.
• Stratification factors: Initial tax liability, tax code submitted, electronic submission, gender, parental status, marital status, voivodship, and age group.
• Data source: Administrative data from the Polish Tax Office.
• Statistical model: Intention-to-treat (ITT) analysis using a regression model:
  $$
  Y_i = T_i \beta + X_i \gamma + u_i
  $$
  Where:
  • $Y_i$ is the payment outcome
  • $T_i$ is the treatment vector
  • $X_i$ is a vector of control variables
  • $u_i$ is the error term
  • Estimated using ordinary least squares (OLS) with robust standard errors.

Cost-Benefit Analysis

• Revenue increase: PLN 39,328,742 if the most effective letter was sent to all taxpayers.
• Cost comparison: Cost of sending letters was significantly lower than the revenue generated, making the intervention highly cost-effective.

Conclusion

Behavioral insights can be effectively used to improve tax compliance in Poland. The experiment demonstrated that:

• Behavioral letters significantly increased tax compliance.
• Hard-tone messages were more effective than soft-tone messages.
• Message effectiveness varied by taxpayer characteristics.
• Regular mail was as effective as registered mail.
• Behavioral interventions are a cost-effective tool for tax authorities, offering a low-cost alternative to traditional reforms.

This report supports the use of behavioral economics in public policy, particularly in tax administration, to enhance compliance and efficiency.