performance rate
The degree of performance is an assessed percentage surcharge or deduction for a human work performance measured in time and is used to "normalize individual performance characteristics when transferred to 'collectives'". The level of performance cannot be measured, but has to be assessed by a trained work organizer (formerly: work student) during a REFA time recording .
Definition in work studies
When two people perform the same task , there is often a difference in the result, i.e. what has been produced or performed. This difference can be explained by the intensity and effectiveness of their work based on the different abilities , skills and willingness to perform of the workers . If such work performance is to be measured, then, in addition to performance and time measurement, a factor must be assessed that compensates for these differences. This factor is called the power factor or, expressed as a percentage, the degree of efficiency.
By applying such a performance level to measured work performance, a reference performance (100% performance) is generated that can be used as a standard time for other workers, as a basis for determining remuneration and as a target time for similar tasks. The REFA association defines the reference service as
“ The performance on which a target time is based is referred to as the reference performance. In general, the reference power receives the degree of performance 100% "
So is
You can also specify the degree of efficiency as a power factor. In this case applies
These equations can only apply if the seven system factors of the work system largely agree. The output referred to here means the volume output, i.e. output / time. If you expand the formulas with it, the result is
This is how the REFA association defines:
“ The degree of performance expresses the ratio of the influenceable actual to the influenceable reference quantity output in percent. "
This very theoretical consideration leads to the practical problem of assessing the degree of performance.
Performance assessment
The rate of return is after the REFA -Methodenlehre one to judging the criteria in time trials . The degree of performance expresses the ratio of an imaginary work performance, viewed as the permanent performance limit, to that just observed.
The pace rating is the methodologically most controversial part of the REFA time recording. Since the human performance in a time recording can be conditioned or deliberately systematically falsified by the circumstances of the observation, a corrective is needed. The result of a time recording should generally be used as a target time for calculations and planning or even as a default time in a performance fee. Thus, on the one hand, it must not overtax people, on the other hand, it must not overreach the company. In addition, the result should lead to reproducible values, i.e. two timekeepers must come to a comparable result independently of one another. REFA describes it as follows:
" The degree of performance assessment consists in the fact that the study worker observes the appearance of the movement sequence and compares it with the image of the presented movement sequence in order to draw a conclusion from this relationship about the presumably achieved quantity performance in relation to the reference quantity performance. "
Procedure for assessing the degree of performance
The assessment is based on the assumption that the timekeeper has precise knowledge of the work process and, based on his training, has a sufficiently good idea of what the sequence of movements would have to look like if the worker did the work for eight hours without slackening the pace and without additional fatigue wanted to perform through work. He assesses this on the basis of the speed ( intensity ) and the ability of the worker ( effectiveness ) in order to determine the deviation from the presented reference performance. Such an assessment cannot be measured. However, through thorough training and practice, a timekeeper can ensure that his results differ only slightly from those of a group of other timekeepers.
The criteria for speed (intensity) mentioned by REFA are strongly dependent on the work process and in some cases cannot be separated from effectiveness at all; the effect of a hammer blow is directly dependent on the speed of execution. On the other hand, REFA names a large number of criteria for effectiveness:
“ Effectiveness is an expression of the quality of the worker's way of working. The effectiveness can be recognized by how familiar, swift, controlled, harmonious, safe, unconscious, calm, purposeful, rhythmic, relaxed work is done. "
The timekeeper therefore creates an idea of what such a performance looks like, sets this "image" equal to 100% (reference performance), compares what the worker is currently doing with it and assesses whether and how much this is faster or slower than his 100% performance .
Dealing with strongly differing levels of performance
The objective of the time recording, namely to determine a time for average suitable and experienced workers, excludes the observation of extremely deviating processes.
The assessable range starts at 80% and goes in steps of five (ie 85, 90, 95 ...) to 120%. In addition, particularly experienced timekeepers can assess performance levels of up to around 135% realistically. However, this requires the timekeeper to have a very high level of experience, which results from a special exercise in assessing various activities - ideally in different industries. Achievements that are below or above these limits are extremely difficult to assess.
Usually a timekeeper will observe such extreme processes, but mark them as not usable in the time study, provided the time recording is carried out cyclically, i.e. on several equal parts, and an average time per unit is then obtained. Such discarding of time values is not always possible in the case of work processes that are tedious and only carried out once. In order to limit the effect of a one-time low level of performance below 80% on a total time in such a case, the assessment of the level of performance should be carried out on as many measured values as possible in order to increase the proportion of times with realistic and qualitatively well assessed levels of performance . The time deviation due to an inaccurate degree of performance assessment below 80% is then negligible in relation to the total execution time of the process.
If an observed performance is permanently outside the permissible assessment range, a time study should be discontinued and continued with a more suitable worker, or better: repeated. The cause of persistently low performance levels is usually a lack of practice and instruction by the employee or, in very rare cases, refusal to perform. A lack of practice is usually also noticeable through frequent interruptions in the process for orientation.
Measurability of the degree of performance
Since the level of performance arises from a complex mixture of intensity and effectiveness, the interaction of which is difficult to measure and therefore cannot be objectified, we speak of assessment today . The previously common term “ efficiency rating estimation ” is incorrect because an estimated value can in principle be measured. The subjectivity of the performance assessment is inevitable and admitted. It is therefore necessary to train timekeepers in such a way that they arrive at the most consistent judgments possible. That this is possible is shown regularly in the relevant training courses. Such training and experience make a good timekeeper.
Frequency of performance assessments
Performance grades should be assessed as often as possible during a time study in order to compensate for errors due to subjectivity and the system of assessment in 5% steps according to Gauss's law of error compensation (the total error is less than the individual errors).
Degree of performance and time degree
Often the term efficiency rate is incorrectly equated with the term time rate and the efficiency levels of a time study are compared with the time rate. However, the level of performance is only assessed for main and secondary jobs. The efficiency ratio, on the other hand, relates to a quantity output in a period.
The degree of performance has an influence on the main and secondary times of a specified time. In addition, waiting times - always 100% - are included in the basic time . Thus, only part of the basic time is influenced by the performance level assessment. A factual and a personal distribution time in the form of percentage surcharges is added to the measured basic time , which ideally are obtained in a distribution time study, but are very often the result of a company exercise or result from a collective agreement. The resulting total time, the time per unit, is then the basis for calculating the degree of time.
Newer use of the term
In process costing - apparently through the translation of the English term "level of performance" into German as "achievement grade" - a meaning seeps into the language, which means the relationship between the service provided and the possible service. In fact , although the term is by definition only referring to humans , a translation with time grade would be more appropriate.
The key figure definition "Level of Performance" is so far neither clear nor complete in English and, in view of the incorrect translations, certainly not in German.
In view of the linguistic power of definition associated with the market significance in this context, a considerable alternative is the “ degree of use ” in the sense used by SAP AG: as an expression for the loss of a capacity - which can also be a human being - from technical and organizational disruptions. In working studies, this size corresponds to the distribution time .
History of performance level
As early as the end of the 19th century, scientific management researched the observation that individual workers carried out an activity faster than others. Taylor took this as an opportunity to systematically search for the so-called “one best way” of a work execution by means of time records in order to then standardize this together with a standard time and to instruct the respective employees accordingly.
Since 1911 there has been a system for assessing performance levels according to the American engineer Charles Bedaux (1886–1944). For the first time, he separated the degree of performance into the components “speed of movement” and “effectiveness” and refined the norms for recovery time supplements .
The problem was taken up by Frank Bunker Gilbreth (1886-1924) and his wife Lillian , who contributed further parts to the solution with movement studies ( Applied Motion Study , 1917) and fatigue studies ( Fatigue Studies , 1918).
See also
Individual evidence
- ↑ Christopher Schlick / Ralph Bruder / Holger Luczak, Arbeitswissenschaft , 3rd completely revised and expanded edition, Heidelberg: Springer, 2010, p. 674 - - ISBN 978-3-540-78332-9 .
- ↑ a b c d e REFA Association for Work Studies and Business Organization (ed.): Methodology of Work Studies: Part 2 - Data determination . Munich: Hanser, 1978. - ISBN 3-446-12704-6 . Page 125 ff.
- ↑ REFA Association for Work Studies and Business Organization (ed.): Methodology of Work Studies: Part 1 - Basics . Munich: Hanser, 1984. - ISBN 3-446-14234-7 . Pages 107–111.
- ↑ a b REFA Association for Work Studies and Business Organization (Ed.): Methodology of Work Studies: Part 1 - Basics . Munich: Hanser, 1984. - ISBN 3-446-14234-7 . Page 27.