The Issue Focus of Online and Television Advertising in the 2016 Presidential Campaign

Theories of campaign issue emphasis were developed in a pre-digital era. How well do these theories explain spending in the current era, when digital media allow for targeting of specific types of voters? In this research, we compare how the 2016 campaigns, both primary and general election, deployed television advertising with how they deployed online advertising. We suggest that, because online messages are targeted to specific viewer profiles much more than television messages, television ads should be more likely to discuss highly salient issues and valance issues than online ads. To test these ideas, we rely upon data from the Wesleyan Media Project, which tracked all televised political ads that aired in 2016, and our coding of data from Pathmatics, a company that tracks online advertising. We find, contrary to our expectations, that the predictors of issue discussion online and on television are largely similar

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data