This is a lot less complicated than it appears. Given a set of sentences, each belonging to a class, and a new input sentence, we can count the occurrence of each word in each class, account for its commonality and assign each class a score. Factoring for commonality is important: matching the word “it” is considerably less meaningful than a match for the word “cheese”. The class with the highest score is the one most likely to belong to the input sentence. This is a slight oversimplification as words need to be reduced to their stems, but you get the basic idea.
The classification score produced identifies the class with the highest term matches (accounting for commonality of words) but this has limitations. A score is not the same as a probability, a score tells us which intent is most like the sentence but not the likelihood of it being a match. Thus it is difficult to apply a threshold for which classification scores to accept or not. Having the highest score from this type of algorithm only provides a relative basis, it may still be an inherently weak classification. Also the algorithm doesn’t account for what a sentence is not, it only counts what it is like. You might say this approach doesn’t consider what makes a sentence not a given class.
By 2022, task-oriented dialog agents/chatbots will take your coffee order, help with tech support problems, and recommend restaurants on your travel. They will be effective, if boring. What do I see beyond 2022? I have no idea. Amara’s law says that we tend to overestimate technology in the short term while underestimating it in the long run. I hope I am right about the short term but wrong about AI in 2022 and beyond! Who would object against a Starbucks barista-bot that can chat about weather and crack a good joke?
However, if you’re trying to develop a sophisticated bot that can understand more than a couple of basic commands, you’re heading down a potentially complicated path. More elaborately coded bots respond to various forms of user questions and responses. The bots have typically been “trained” on databases of thousands of words, queries, or sentences so that they can learn to detect lexical similarity. A good e-commerce bot “knows” that trousers are a kind of pants (if you are in the US), though this is beyond the comprehension of a simple, untrained bot.
Note — If the plan is to build the sample conversations from the scratch, then one recommended way is to use an approach called interactive learning. We will not go into the details of the interactive learning here, but to put it in simple terms and as the name suggests, it is a user interface application that will prompt the user to input the user request and then the dialogue manager model will come up with its top choices for predicting the best next_action, prompting the user again to confirm on its priority of learned choices. The model uses this feedback to refine its predictions for next time (This is like a reinforcement learning technique wherein the model is rewarded for its correct predictions).

Alexander J Porter is Head of Copy for Paperclip Digital - Sydney’s boutique agency with bold visions. Bringing a creative flair to everything that he does, he wields words to weave magic connections between brands and their buyers. With extensive experience as a content writer, he is constantly driven to explore the way language can strike consumers like lightning.
An AI-powered chatbot is a smarter version of a chatbot (a machine that has the ability to communicate with humans via text or audio). It uses natural language processing (NLP) and machine learning (ML) to get a better understanding of the intent of humans it interacts with. Also, its purpose is to provide a natural, as near human-level communication as possible.
According to this study by Petter Bae Brandtzaeg, “the real buzz about this technology did not start before the spring of 2016. Two reasons for the sudden and renewed interest in chatbots were [number one] massive advances in artificial intelligence (AI) and a major usage shift from online social networksto mobile messaging applications such as Facebook Messenger, Telegram, Slack, Kik, and Viber.”
As VP of Coveo’s Platform line of business, Gauthier Robe oversees the company’s Intelligent Search Platform and roadmap, including Coveo Cloud, announced in June 2015. Gauthier is passionate about using technology to improve customers’ and people’s lives. He has over a decade of international experience in the high-tech industry and deep knowledge of Cloud Computing, electronics, IoT, and product management. Prior to Coveo, Gauthier worked for Amazon Web Services and held various positions in high-tech consulting firms, helping customers envision the future and achieve its potential. Gauthier resides in the Boston area and has an engineering degree from UCL & MIT. In his spare time, Gauthier enjoys tinkering with new technologies and connected devices.
The classic historic early chatbots are ELIZA (1966) and PARRY (1972).[10][11][12][13] More recent notable programs include A.L.I.C.E., Jabberwacky and D.U.D.E (Agence Nationale de la Recherche and CNRS 2006). While ELIZA and PARRY were used exclusively to simulate typed conversation, many chatbots now include functional features such as games and web searching abilities. In 1984, a book called The Policeman's Beard is Half Constructed was published, allegedly written by the chatbot Racter (though the program as released would not have been capable of doing so).[14]