Given the regulatory requirement to publish unaudited annual financial statements before the audited versions in Iran's capital market and the significant discrepancies between the two, this study examines the interactive effect of investors' experience and changes in post-audit net income on the perceived credibility of three key pillars of financial reporting (audited financial statements, management, and independent auditors). A 2×2 between-subjects experimental design (investment experience: low/high; income change: increase/decrease) was employed, with 119 finance graduates as investor participants. Data were collected via an online questionnaire in August 2024 and analyzed using rank ANOVA in SPSS-24. Results reveal that investors with low experience, reacting to a post-audit decline in net income, assign lower credibility to audited financial statements and independent auditors, whereas experienced investors remain unaffected by such changes. Notably, regardless of experience level or income change, investors consistently rated managers’ credibility lower than that of auditors. These findings underscore the need for investor education and enhanced audit process transparency to mitigate perceptual gaps across investor groups.

Introduction

This study investigates how discrepancies between unaudited and audited financial statements—specifically, changes in net income following the audit process—influence the credibility assessments of investors with varying levels of investment experience. According to the executive bylaws of the Tehran Stock Exchange (since 2007), listed companies are mandated to disclose unaudited annual financial statements within 60 days of their fiscal year-end. However, the release of audited statements can be delayed until 110 days after the year-end. This dual-disclosure framework creates a unique informational environment. The early release of unaudited statements enhances transparency and mitigates information asymmetry by providing stakeholders with preliminary financial data. Conversely, the subsequent audited version offers a more reliable representation of the company's financial status. While this process aims to ensure a continuous information flow to the market, the existence of material differences between the two versions can pose significant challenges for investors. This research focuses on how these post-audit income changes affect investors' perceptions of the credibility of three pillars of financial reporting: company management, the independent auditor, and the audited financial statements. Understanding these dynamics is crucial for evaluating the effectiveness of current disclosure policies and for developing measures to enhance market efficiency and protect investor interests.
 

Literature Review

This research is grounded in the tension between rational-assurance theory and cognitive psychology. The rational perspective posits that audited financial statements inherently possess higher credibility than unaudited versions, and thus, post-audit adjustments should not diminish their perceived credibility (Hodge, 2001; Libby, 1979; Mercer, 2004). Conversely, cognitive psychology, through the lens of negativity bias, predicts that investors weigh negative information more heavily, meaning that a post-audit earnings decrease could damage the credibility of the final financial statements (Baumeister et al., 2001; Pratto & John, 1991). This effect is compounded by investors' tendency to integrate audited and unaudited information (Hodge, 2001). A key moderating factor is investor experience. Experienced investors, shaped by adaptive market learning (Lo, 2004), typically develop a better ability to control emotional reactions to negative news (Gervais & Odean, 2001). Novice investors, however, are more susceptible to cognitive biases. Furthermore, the self-serving attribution theory (Heider, 1958) explains how investors assign blame: novices are more likely to attribute negative outcomes (like an earnings decrease) externally to management or the auditor, while experienced investors may make more internal attributions (Gervais & Odean, 2001; Dhar & Zhu, 2006). Based on this framework, the study tests the following hypotheses:
H1: A decrease in post-audit net income reduces the credibility of audited financial statements more for novice investors than for experienced investors.
H2: Novice investors will assign lower credibility to audited financial statements following a decrease in post-audit net income compared to an increase.
H3: A decrease in post-audit net income reduces the credibility of company management more for novice investors than for experienced investors.
H4: Novice investors will assign lower credibility to company management following a decrease in post-audit net income compared to an increase.
H5: A decrease in post-audit net income reduces the credibility of the independent auditor more for novice investors than for experienced investors.
H6: Novice investors will assign lower credibility to the independent auditor following a decrease in post-audit net income compared to an increase.
 

Research Methodology

This experimental study employed a 2x2 between-subjects design to investigate how investment experience (inexperienced/experienced) and post-audit net income changes (12% increase/decrease) influence investors' credibility judgments. Using an online questionnaire, 119 finance graduates, recruited via LinkedIn, were randomly assigned to one of four conditions. Participants, acting as current investors in a hypothetical firm, reviewed unaudited and subsequently manipulated audited financial statements. Their assessments of the credibility of the audited statements, company management, and the independent auditor were then measured using validated Likert scales, with data analyzed using rank-based ANOVA to ensure robustness.
 

Results and Discussions

The results revealed a significant interaction effect between investor experience and post-audit income change on the perceived credibility of audited financial statements (F = 9.413, p<0.01). As hypothesized, novice investors significantly downgraded their credibility assessment when faced with a 12% decrease in post-audit income (Mean = 6.15) compared to an increase (Mean = 7.97, p<0.01), while experienced investors' judgments remained stable (Mean = 7.88 vs. 7.41, p=0.368), confirming that experience mitigates negativity bias. For auditor credibility, a similar pattern emerged: novices assigned significantly lower credibility to auditors following an income decrease compared to experienced investors (Mean = 6.72 vs. 7.52, p = 0.035), aligning with self-serving attribution theory, where novices externalize blame. Conversely, the credibility assessments of company management were unaffected by either experience or income change, suggesting a persistent, underlying distrust in management among all investors, regardless of experimental conditions.
 

Conclusions

This study demonstrates that investor experience critically moderates reactions to discrepancies between unaudited and audited net income. Novice investors, influenced by negativity bias, significantly downgraded their credibility assessments of both audited financial statements and the independent auditor following a post-audit net income decrease, while experienced investors' judgments remained stable. This aligns with cognitive theories in which novices disproportionately externalize blame for negative outcomes. Notably, the credibility of company management remained persistently low across all conditions, indicating a deep-seated, structural distrust in management that is unaffected by positive news or investor sophistication. These findings highlight a vulnerability among retail investors in emerging markets like Iran, where the mandatory early release of unaudited statements can lead to significant reassessments upon audit completion. For regulators and standard-setters, this underscores the need for enhanced investor education and potentially revised disclosure timelines to mitigate the cognitive biases uncovered. Future research should explore different magnitudes of earnings adjustments and incorporate varied auditor opinion types to further generalize these findings.