A popular technique for investigating causes and effects is known as a _____ diagram.

The fishbone diagram, also known as an Ishikawa diagram or cause-and-effect diagram, is a popular tool used for identifying and analyzing the potential causes of a specific problem or effect. This technique is especially valuable in quality control and process improvement because it visually organizes and categorizes various factors contributing to an issue.

The structure of the fishbone diagram resembles the skeleton of a fish, where the "head" represents the main problem or effect, and the "bones" branching off represent different categories of causes. Typically, these categories might include people, processes, materials, equipment, and environment. By mapping out all possible causes in this visual format, teams can better identify root causes and develop targeted solutions.

This method facilitates group brainstorming, encourages thorough exploration of potential factors, and clarifies relationships between causes and their effects, making it an effective strategy in understanding complex issues. Thus, the fishbone diagram is a crucial tool in systems analysis and problem-solving contexts, cementing its place as the correct answer.