Statistics for complex problems
In practice, problems are rarely well-defined and there may be various different ways to collect data to throw light on them.
Collection and analysis of data to help attack the problem usually suggest further questions for which further data are required. Several cycles of data collection and analysis are usually needed, with considerable input from an expert in the problem area between each cycle of the process.
Continuous quality improvement
In business and industry, statistics is an important part of the long-term monitoring of performance. We may simply want to ensure that systems continue to perform at their current levels, or the aim may be to improve aspects of the system. The latter is often called continuous quality improvement or total quality management.
Problems in a process are usually detected by collecting and analysing data about the performance of the system. This section describes the use of control charts as a way to monitor processes.