What is an inherent methodological weakness associated with salary data gathered via self-reported surveys on popular websites?

Answer

There is an inherent psychological tendency for individuals to inflate figures or omit certain compensation details.

When individuals voluntarily submit salary information, they may inflate figures due to feelings of being underpaid, or conversely, omit non-base pay components like bonuses if the survey does not explicitly ask for them, leading to systemic skew.

What is an inherent methodological weakness associated with salary data gathered via self-reported surveys on popular websites?
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