ME at the Margins: Average Marginal Effects, Marginal Effects at the Mean, and Stata’s margins command

Seems that my students and I are not the only ones who are occasionally baffled by Stata’s margins command, which does all sorts of amazing things. Margins is incredibly powerful, and the accompanying marginsplot command almost always does just the right thing. These commands come with excellent documentation, but at a mere 58 pages (not…

Failing better in Stata

The Stata idiom capture quietly makes it so that any output from the subsequent command is suppressed, and that even critical failures are happily ignored. Your script soldiers on, and you are none the wiser. I always thought that this is a wonderful metaphor for organisational behaviour. In unrelated news, every other summer, Statacorp comes…

Surveybias 1.4 is out

Surveybias 1.4 is out 6

Just how badly biased is your pre-election survey? Once the election results are in, our scalar measures B and B_w provide convenient, single number summaries. Our surveybias add-on for Stata will calculate these and other measures from either raw data or from published margins. Its latest iteration (version 1.4) has just appeared on SSC. Surveybias…

“Strukturgleichungsmodelle für Politikwissenschaftler” erschienen

In der letzten Woche ist meine Einführung zum Thema Strukturgleichungsmodelle bei Springer/VS erschienen. Das Buch zeigt, wie sich die gängigsten Modelle (u.a. einfache und Mehr-Gruppen-Konfirmatorische-Faktorenanalysen (CFA/MGCFA)) in Stata, Lisrel und MPlus realisieren lassen. Die Beispiele stammen aus dem Bereich der politikwissenschaftlichen Einstellungsforschung (Fremdenfeindlichkeit, politische Entfremdung, politisches Interesse …). Alle Beispieldateien können hier heruntergeladen werden. Das…

New (Free!) Software for Assessing Survey Bias

Worried about survey bias? We have updated our add-on (or ado) surveybias, which calculates our multinomial generalisation of the old Martin, Traugott, and Kennedy (2005) measure for survey bias. If you have any dichotomous or multinomial variable in your survey whose true distribution is known (e.g. from the census, electoral counts, or other official data),…