A verbal model is a translation of the mental model. Therefore, mental/verbal model expresses all of the functional relationships between the variables in a word passage. For example, consider the advertising manager of a company that manufactures breakfast cereal who makes the following statement concerning television commercials on Saturday morning: "A 20-second spot has much more impact on our target audience than a 15-second spot." In this example, the different time duration's of the commercial are the decision alternatives; its "impact" which, we could infer, relates to the propensity of the viewers' parents to purchase the company's cereal, is the dependent variable. Thus, we have a relationship between decision alternatives and a dependent variable that relates to company objectives. Such models are used extensively in the business world and have the advantage of being easy to understand. Often they are an outcropping of many years of managerial experience and are useful for summarising this experience in understandable language.
Mental/verbal models, however, have a number of shortcomings. The decision-maker cannot experiment with them, nor do they indicate specifically how the outcomes or measures of effectiveness change with the decision alternatives. In the preceding mental/verbal model, we do not know how much more impact a 20-second commercial has over a 15-second commercial. The other drawback is that it is not easy to show how the relationships change with the decision alternative. If we constructed a mental/verbal model that answered such questions for all possible commercial lengths, we would have a very lengthy mental/verbal model that would be difficult to understand and not useful for experimentation. Nevertheless, mental/verbal models can play an important role in the decision process. They can be used to verbalise decision strategies from more sophisticated models.