What is work sampling?
Posted: Thu Jan 23, 2025 4:56 am
Work sampling (also known as activity sampling or statistical activity control) is a technique to determine, through statistical sampling and random observations, the percentage of occurrence of a certain activity.
Why do we do it? We do it so that, for example, when we want to determine the productive and inactive time of the machines in a workplace, we do not have to spend all day observing the operation of the machines, noting the time and cause of an interruption. Instead, we can make N trips around the factory randomly, recording the machines that are working, those australia phone number list are stopped, and the reasons why they do so.
In this way, when the sample size is representative of the population and the observations are made at random, we can consider under a certain level of confidence that the observations are a reflection of the real situation in the factory.
Why carry out work sampling?
We do this to determine:
How much personnel or machinery is being used.
Slack, understood as the time available to carry out an activity without delaying production.
Production standards.
How is this possible? The law of probability and its relation to work sampling
With this clear, we can go directly to how to do a work sampling, but I think it is convenient that you first understand what the bases are, so if you want, study a little the following concepts: law of probabilities, normal curve and confidence level.
How to perform work sampling
Step 1: Select the activities or activities to observe and socialize
Clearly, this is step 1. It is important that the workers involved are aware of what is going to be done for the proper development of the exercise.
In addition to socializing, we also define the activities that are the object of the study. Maybe we want to know the percentage of time that a machine is running, stopped, or being repaired. Maybe we want to know what percentage of a salesperson's time is spent selling by phone, selling in person, attending meetings, doing paperwork, and doing leisure activities. Knowing this is necessary to prepare the form to be filled out, since this will depend on the objectives of the study.
Finally, you must think about and decide on the conditions that may arise during sampling to avoid ambiguities. For example, if you are doing work sampling in a hospital for the nursing area and the nurse talks to a patient about non-medical aspects, does it count as work or is it non-productive time? If the engine of a forklift is running while it is loading and unloading, is it running or stopped?
Why do we do it? We do it so that, for example, when we want to determine the productive and inactive time of the machines in a workplace, we do not have to spend all day observing the operation of the machines, noting the time and cause of an interruption. Instead, we can make N trips around the factory randomly, recording the machines that are working, those australia phone number list are stopped, and the reasons why they do so.
In this way, when the sample size is representative of the population and the observations are made at random, we can consider under a certain level of confidence that the observations are a reflection of the real situation in the factory.
Why carry out work sampling?
We do this to determine:
How much personnel or machinery is being used.
Slack, understood as the time available to carry out an activity without delaying production.
Production standards.
How is this possible? The law of probability and its relation to work sampling
With this clear, we can go directly to how to do a work sampling, but I think it is convenient that you first understand what the bases are, so if you want, study a little the following concepts: law of probabilities, normal curve and confidence level.
How to perform work sampling
Step 1: Select the activities or activities to observe and socialize
Clearly, this is step 1. It is important that the workers involved are aware of what is going to be done for the proper development of the exercise.
In addition to socializing, we also define the activities that are the object of the study. Maybe we want to know the percentage of time that a machine is running, stopped, or being repaired. Maybe we want to know what percentage of a salesperson's time is spent selling by phone, selling in person, attending meetings, doing paperwork, and doing leisure activities. Knowing this is necessary to prepare the form to be filled out, since this will depend on the objectives of the study.
Finally, you must think about and decide on the conditions that may arise during sampling to avoid ambiguities. For example, if you are doing work sampling in a hospital for the nursing area and the nurse talks to a patient about non-medical aspects, does it count as work or is it non-productive time? If the engine of a forklift is running while it is loading and unloading, is it running or stopped?