About the Authors

Raúl Jiménez

rauljose.jimenez@uc3m.es

Affiliation Department of Statistics, Universidad Carlos III de Madrid, Getafe, Madrid, Spain

Manuel Hidalgo

Affiliation Department of Social Sciences, Universidad Carlos III de Madrid, Getafe, Madrid, Spain

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Analyzed the data: RJ. Wrote the paper: RJ MH.