From: Habitat-related differences in song structure and complexity in a songbird with a large repertoire
 | Variable | Urban 95% CI | Forest 95% CI | t/Z | p |
---|---|---|---|---|---|
A | Whistle minimum frequency | 2465.4–2538.9 | 2312.0–2421.7 | 3.778 | < 0.001 |
 | Whistle peak frequency | 2978.0–3112.5 | 2803.6–2945.9 | 3.369 | 0.001 |
 | Twitter minimum frequency | 3939.2–4254.6 | 3823.2–4051.1 | 1.725 | 0.090 |
 | Twitter peak frequency | 5149.8–5459.2 | 5008.9–5262.4 | 1.725 | 0.090 |
B | Syllable repertoire | 343.58–422.85 | 276.05–335.72 | 3.246 | 0.002 |
 | Whistle repertoire | 117.78–146.48 | 97.89–118.96 | 2.787 | 0.007 |
 | Twitter repertoire | 216.14–286.04 | 172.83–222.08 | 2.649 | 0.010 |
 | Twitter fraction | 433.06–543.64 | 366.31–462.49 | 2.035 | 0.047 |
C | Syllable duration | 0.10–0.11 | 0.10–0.11 | − 0.337 | 0.737 |
 | Inter-syllable intervals | 0.33–0.42 | 0.36–0.45 | − 0.715 | 0.474 |
 | Syllable rate | 122.19–145.07 | 116.64–136.93 | 0.898 | 0.373 |
 | Redundancy index | 0.20–0.24 | 0.22–0.26 | − 1.138 | 0.260 |
 | Linearity index | 0.44–0.54 | 0.36–0.44 | 2.811 | 0.007 |