Erratum: Axel Bruns and Stefan Stieglitz (2013) Towards more systematic Twitter analysis: metrics for tweeting activities International Journal of Social Research Methodology, XX(X), pp. 1–18. … Original post: Erratum: Axel Bruns and Stefan Stieglitz (2013) Towards more systematic Twitter analysis: metrics for tweeting activities International Journal of Social Research Methodology, XX(X), pp. 1–18.