Determination of standard output/piece rates

How are output rates or piece rates determined under labor law? The standard output rates or piece rates shall be determined through any of the following procedures:

[1] Time and motion studies;
[2] An individual/collective agreement between the employer and its workers as approved by the DOLE Secretary or his authorized representative; or
[3] Consultation with representatives of employers’ and workers’ organizations in a tripartite conference called by the DOLE Secretary.