Robust measures of scale for shot length distributions

This week I have written a short paper on robust measures of scale for shot length distributions. The statistical analysis of film style has typcially focussed on questions of location rather than the dispersion of shot lengths in a motion – understanding how the variation in shot lengths has changed is as important as understanding how editing has speeded up or slowed down over time.  Just as we need robust measures of location (e.g. the median shot length) we also need robust measures of dispersion, and in this paper I look at six possible statistics that could be used. The paper can be downloaded here as a pdf file:

Nick Redfern – Robust measures of scale for shot length distributions

The shot length data for the three Laurel and Hardy films that I refer was collected by me as part of a larger study, and when I finally finish it off I will post the draft of my Laurel and Hardy essy along with the complete shot length data for all the films I have looked.

Many of the papers on statistical methodology that I cite can be accessed for free over the internet, and if anyone is interested in the statistical analysis of film style then I recommend reading the papers on robust statistics before proceeding as this will save you a lot of trouble in the long run. The references, with links to online versions of the papers are:

Croux C and Rousseeuw PJ 1992 Time-efficient algorithms for two highly robust estimators of scale, Computational Statistics 1: 411-428.

Daszykowski M, Kaczmarek K, Vander Heyden Y, and Walczak B 2007 Robust statistics in data analysis – a review: basic concepts, Chemometrics and Intelligent Laboratory Systems 85: 203-219.

Gorard S 2004 Revisiting a 90-year-old debate: the advantages of the mean deviation, British Educational Research Association Annual Conference, University of Manchester, 16-18 September 2004:, accessed 15 July 2010.

Rousseeuw PJ 1991 Tutorial to robust statistics, Journal of Chemometrics 5: 1-20.

Rousseeuw PJ and Croux C 1993 Alternatives to median absolute deviation, Journal of the American Statistical Association 88: 1273–1283.

About Nick Redfern

I am an independent academic with over 15 years experience teaching film in higher education in the UK. I have taught film analysis, film industries, film theories, film history, science fiction at Manchester Metropolitan University, the University of Central Lancashire, and Leeds Trinity University, where I was programme leader for film from 2016 to 2020. My research interests include computational film analysis, horror cinema, sound design, science fiction, film trailers, British cinema, and regional film cultures.

Posted on July 15, 2010, in Alfred Hitchcock, Cinemetrics, Film Analysis, Film Studies, Film Style, Laurel and Hardy and tagged , , , , , . Bookmark the permalink. 4 Comments.

  1. I came across this entry from a web search about robust measures of scale. You might like to know that the “R” statistical language has a package that can calculate both Qn and Sn quickly and simply. “R” and associated packages are available at no cost.

  2. There is also a Fortran function for these estimators available through the Statlib software archive:

  1. Pingback: Shot length distributions in German cinema, 1929 to 1933 « Research into film

  2. Pingback: Using the ECDF to analyse film style « Research into film

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