Explain what do you mean by employee group and sub-group.

Employee group 

Each employee group is defined with one-digit identification.

The employee group has the following organizational functions:

• Employee groups allow you to generate data entry default values, for example, for the payroll accounting area or an employee’s basic pay. 
• Employee groups serve as selection criteria for reporting. 
• Employee groups constitute an authorization check unit.

Personnel calculation rule (control whether an employee’s remuneration is calculated on a monthly or hourly basis)

Wage types (determine which wage types are permissible for which employee subgroups using the employee subgroup grouping for the primary wage types)

Collective agreement provision (you restrict the eligibility of pay scale groups, so that only certain pay scale groups are valid for specific employee subgroups)

Work schedules (determine which work schedules are permissible for which employee subgroups using the employee subgroup grouping for the work schedule.
Determine which work schedules are permissible for which employee subgroups using the employee subgroup grouping for the work schedule)

Appraisal criteria (set up appraisal criteria dependent on employee subgroup using the employee subgroup grouping)

The employee subgroup enables you to define data entry default values, for example, for the payroll area or an employee’s basic pay. 

The employee subgroup is a selection criterion for evaluations. 

Employee subgroups are an authorization check unit.

SAP Human Resource Books
SAP HR Books - Certification, Interview Questions and Configuration

SAP Human Resource Tips
SAP HR Tips and Human Resource Management

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