Inference Engine
An inference engine is a core component of expert systems designed to apply logical rules to a knowledge base to derive new information or make decisions. It is the 'brain' of an expert system, simulating the human ability to make inferences. Inference engines work by using various algorithms to navigate through the knowledge base, which contains domain-specific facts and rules, and applying these rules to known facts to infer new facts or conclusions.
These engines can operate in different modes, such as forward chaining, where inferences are made from given data to conclusions, or backward chaining, where the engine starts with a hypothesis and works backward to see if data supports the hypothesis. This process allows expert systems to provide explanations and justifications for each conclusion or decision made, closely mimicking human expert problem-solving capabilities.
In a medical diagnosis expert system, the inference engine takes patient symptoms and medical history as input and applies a set of medical rules (if-then-else conditions) stored in the knowledge base to infer potential diagnoses. For instance, if a patient has symptoms A, B, and C, and the knowledge base contains a rule that these symptoms together indicate a certain disease, the inference engine can conclude that the patient might have that disease.
Another application is in customer support chatbots, where the inference engine uses the knowledge base containing product information, troubleshooting steps, and customer interaction rules to respond to customer queries and resolve issues by inferring the most relevant solutions based on the input received from the customer.