What Is Convenience Sampling?

Arbitrary sampling is a method by which auditors randomly select a part of the overall review as a sample for review and audit. It is an audit sampling method used in the early stage of modern audit development. This sampling method does not have a certain law on the number and content of samples, and it has no scientific basis. It has a great chance and it is difficult to guarantee the quality of the audit work, just to reduce the audit workload. With the development of modern audit, "arbitrary sampling" has gradually evolved into "judgment sampling". ^[1]

The basic theoretical basis of arbitrary sampling is that each unit of the surveyed population is assumed to be the same. If the homogeneity of the overall units is obvious, this method will achieve better results.

Arbitrary sampling is the simplest and most cost-effective way of non-random sampling, which can quickly obtain relevant information. But its contingency is relatively large, because people who meet at a certain time and place are very accidental. Therefore, the reliability of the obtained data is low, the sample is poorly represented, and the error is also large.

Arbitrary sampling is mainly used for exploratory surveys, or some surveys with high timeliness requirements; populations with obvious flow characteristics and unclear boundaries. ^[2]

Arbitrary sampling, also called convenience sampling, is a sampling method based on the convenience of the investigator. "Street blocking" and "space sampling" are the two most common methods for convenient sampling.

The "street blocking method" is to find any pedestrian on the street or at an intersection, and use it as a subject for investigation. For example, ask pedestrians on the street their views on market prices, ask pedestrians to fill in some questionnaires, and so on.

The space sampling method is to sample a certain group of people from different directions and orientations of the space, such as asking customers for opinions on the service quality of the mall in the mall; surveying migrant workers in the labor market.

Arbitrary sampling is simple and easy to obtain the required information and materials in a timely manner, which saves time, labor and money, but the sampling bias is large, and it is generally used for informal exploratory surveys. When it is large, the sample drawn is highly representative. ^[4]

Arbitrary sampling technology is simple and easy, and can obtain the required information in time, saving time and costs. From the perspective of convenience of work, investigators randomly select a certain number of samples within the scope of the survey objects for investigation. For example, if investigators conduct surveys on the consumption propensity of young Beijing residents, they can directly select classmates or friends as interviewees, immediately conduct surveys, and quickly obtain the data required for survey analysis. This method is simple and easy to implement, and can obtain the required information in time, saving time and costs. ^[3]

However, in practice, not every individual in all populations is the same, so the sampling results have large deviations and low credibility, and its samples are not sufficiently representative.