What is the purpose of a statistical sample?

The purpose of a statistical sample is to quantify the quantity of the entire lot. When dealing with large quantities of materials such as soils or aggregates, it is often impractical or impossible to test every individual item. By taking a statistical sample, inspectors can make inferences about the entire lot based on the characteristics observed in the sample. This approach allows for efficient and effective quality control, ensuring that if the sample meets the required standards, it is reasonable to conclude that the larger lot also meets those standards.

This method relies on statistical principles that help ensure that the sample is representative of the whole, allowing for accurate estimations of properties such as compaction, moisture content, or aggregate gradation across the entire lot without needing to test every item. It emphasizes the effectiveness of targeted sampling in achieving reliable results in a time-efficient manner, which ultimately supports good practices in quality management.