To measure the success of your data models, you need to define some criteria and metrics that reflect your goals and expectations. Depending on the type and purpose of your data model, a variety of metrics can be used to evaluate its quality and usefulness. For example, accuracy can be assessed by comparing your data model with the actual data or with a reference model, and calculating the error rate, the precision, or the recall. Complexity can be determined by counting the number of entities, attributes, and relationships in your data model, or by measuring the depth, width, or density of your data model. Consistency can be measured by checking if your data model follows the rules and standards of your data domain, and if it avoids redundancy, ambiguity, or contradiction. Finally, relevance can be evaluated by asking if your data model answers the questions and solves the problems that you have defined, and if it provides useful and actionable insights.