Invited by IBT's founder and director, Prof. Christian Hildebrand, Prof. Hartmann gave a seminar talk on his project: "To be clear: Ambiguity in multi-modal digital ads can be a double-edged sword". The paper is joint work with Prof. Oded Netzer (Columbia Business School) and Shunyuan Zhang (Harvard Business School). Prof. Hartmann had the opportunity to engage in one-on-one sessions with the PhD students at IBT.