The paper accurately determines zygosity in a twins’ data set, presents a fairly
detailed demographic and socio-economic profile of monozygotic (MZ) and
dizygotic (DZ) twins in the Ghanaian labour market and provides evidence of the
similarities and differences between MZ and DZ twins. Predictive discriminant
analysis is used to classify twins into MZ and DZ groups and descriptive analysis is
performed to observe and explore patterns and relationships between sociodemographic
variables. The discriminant analysis revealed that 99.2% of the twins
were classified correctly into MZ and DZ twins groups. The descriptive analysis
indicated that female twins slightly outnumber male twins and the sample of twins
was largely youthful. It was also observed that more than half of the twins had
completed only elementary schooling. However, MZ twins had higher educational
attainment and higher earnings than DZ twins. The association between the
educational levels and annual earnings of MZ twins were also found to be greater
than that of DZ twins. The findings suggest that genes and environment play a
major role in identifying similarities and differences in the socio-demographic
characteristics of individuals in the workforce.