Automated pitch detection algorithms are used to generate 23 pitch-related and spectral parameters for a collection of caws from 18 wild, marked crows. 
Automated pitch detection algorithms
Using principal component analysis and mixed models, we identify independent axes of acoustic variation associated with behavioural context and with caller sex, respectively. 
principal component analysis
Using principal component analysis and mixed models, we identify independent axes of acoustic variation associated with behavioural context and with caller sex, respectively. 
mixed models