1 INTRODUCTION  
2 BACKGROUND  
3 RADIO GALAXY SAMPLES  
3.1 NVSS  
3.2 RACS-low  
3.3 Summary  
4 APPROACH  
4.1 Expected amplitude  
4.2 Bayesian inference  
5 RESULTS  
5.1 Individual catalogues  
5.2 Joint analysis  
6 DISCUSSION & CONCLUSIONS  
6.1 Effect of local clustering  
6.2 Comparison with other studies  
6.3 Future outlook