What should be used to implement calculation groups in the Research division's semantic models?

To implement calculation groups in the Research division's semantic models, using Tabular Editor is the most appropriate choice because it is specifically designed for working with Tabular models in Microsoft Analysis Services, Azure Analysis Services, and Power BI. Tabular Editor provides a user-friendly interface that allows developers to efficiently create and manage calculation groups, as well as other model artifacts.

Calculation groups are a powerful feature that allows you to define reusable calculations like measures that can change based on the context of other slicers or filters in reports. Tabular Editor supports this feature and makes it easier to structure these groups without the need to write extensive DAX code manually, enabling a more efficient development process and minimizing potential errors.

While Power BI Designer can create and manage various aspects of a model, it doesn't offer the same level of efficiency for creating calculation groups as Tabular Editor. Microsoft Excel, while a powerful tool for data analysis and reporting, does not directly support the implementation of calculation groups in semantic models. DAX Studio is primarily used for writing, executing, and analyzing DAX queries rather than for model management or setup. Therefore, Tabular Editor stands out as the correct choice for this specific task in developing the Research division's semantic models.