Discrimination in this context may refer to either direct exclusion (such as females being prevented from certain occupations in the military) or a restriction in opportunities for promotion (such as promotions being partially determined by the length of continuous tenure thereby excluding primary care givers of families).
Some employers may interpret an individual's request for part-time work as an indication of lower workforce enthusiasm and attachment. As result, it may be argued that just as employers perceive female's potential family responsibilities as a negative asset to the firm, and hence use this as a means of screening them from higher paid management positions, part- time work for both sexes may be similarly treated.
This factors is perhaps the most widely discussed determinant of differences in wages and representation of one group over another. If there exists differences in the level of discrimination which affect certain groups access to different occupations this process is sufficient to produce wage differentials between groups. This arises as a result of the importance of occupations in affecting the wages individuals receive.
There have been several theories developed which attempt to explain the underlying causes of discrimination50. Becker (1957, 1971) developed a model of discrimination which is based on the notion that the
"tastes" of employers and employees are the motivating force behind discrimination. The effect of this taste for discrimination may be ameliorated through compensation. In the case of wages, employers may reduce female wages relative to that of males (or alternatively, increase male wages relative to females) to compensate themselves for their natural disinclination to hire females. Similarly, employers may believe female part-time workers should be at home caring for their child, or do not take their work seriously, and hence may compensate themselves for these factors by lowering the wage of part-time workers. Becker argued that in the case where these compensations are made, resources are being allocated inefficiently, and, in a perfectly competitive market, these inefficiencies would cause discriminating firms to disappear in the long run, thereby eliminating any wage or price differentials which may exist.
In an alternative model, Bergmann (1971, 1974) uses the examples of race and sex discrimination in her model of discrimination. The initial assumption is, like Becker, that employers have some distaste for hiring women or minority groups. In the Bergmann model, the distaste against these groups is so strong that employers explicitly exclude them from jobs. This exclusion leads to an oversupply of the excluded groups to jobs which are deemed appropriate, and it is this excess supply which forces wages down for these jobs relative to their earnings capacity if no discrimination, in the form of occupational segregation, occurred. Since there is a restriction of the movement of workers into jobs where they may have a competitive advantage, resources are not being efficiently allocated. Although this model does not require the somewhat restrictive neoclassical assumptions of the Becker model (such as perfect information, mobility and competition), it has the same conclusion that in the long run discrimination will disappear as a result of the unprofitable effects of excluding the most efficient workers from employment.
The type model of discrimination is a series of models which may be collectively identified as statistical discrimination51. Statistical discrimination occurs when employers discriminate against the perceived negative characteristics of a group as a type of screening mechanism in their employment practices irrespective of the attributes of the individual . In this model, if part-time workers or females are perceived to have higher turnover and hence higher training costs than full-time and males respectively, then this may result in employers being reluctant to employ these groups if all groups were equally available. Additionally, if part-time workers are believed to be less motivated than full-time workers, employers will be less likely to hire individuals who seek part-time work.
This model suggests that employees from the groups perceived as less-desirable will obtain jobs where factors for which the group is regarded as undesirable such as turnover costs are less important. An example would be low-skill jobs. Alternatively, the less-desirable group may obtain some representation in high skill jobs if the wage rate is flexible enough to allow employers to compensate themselves for the additional risk of employing these individuals. Thus, this model also includes an explanation for occupational segregation.
Therefore in this type of discrimination model, employers do not necessarily have a taste for discrimination. However, they believe they are minimising the costs of screening potential employees by eliminating individuals on the basis of the perceptions of the group. The implication is of course, that if these perceptions are incorrect, or if the employer could identify members of the group which were atypical, then it would be advantageous for the employer not to employ statistical discrimination. As a result, in the long-run, employers who evaluate individuals rather than
groups in their selection criteria will be compensated through more productive workers (which exceed the initial screening costs), and hence have a competitive advantage over discriminating employers.