Entities mentioned:
- The Guardian: Professional pride, Transparency, Accountability
- Readers: Justice, Curiosity, Righteousness

Article Assessment:
Credibility Score: 70/100
Bias Rating: 50/100 (Center)
Sentiment Score: 55/100
Authoritarianism Risk: 20/100 (Strongly Democratic)

Bias Analysis:
The article's brevity provides little context for bias assessment. The neutral term 'Open door' suggests a centrist approach to reader engagement, neither leaning left nor right.

Key metric: Media Trust and Accountability

As a social scientist, I analyze that this article, though brief, implies The Guardian's commitment to addressing reader complaints and corrections. This practice positively impacts media trust and accountability by demonstrating openness to feedback and willingness to correct errors. Such transparency can enhance public trust in journalism and promote media literacy.