When Ruth Clark considers the available evidence in favor of active learning over lecture, she presents a summarized bar chart comparing the effectiveness of lecture against other forms of instruction to achieve various instructional ends. It looks like this.
I really like Clark’s book, but one element of this chart caught my eye that I didn’t think was fair. In terms of using the most economical instructional technique that meets the objective, lecture, all else being equal, is the one to beat. Lectures deliver high volumes of information quickly, are cheaper to develop than more active approaches, and often are more comfortable for subject matter experts to deliver. Thus, another technique in a given situation would have to be demonstrably better than lecture, not just equal.
Thus, I think the bar chart would have been fairer to show this way: