Hey, people are doing the multiverse!

Elio Campitelli writes:

I’ve just saw this image in a paper discussing the weight of evidence for a “hiatus” in the global warming signal and immediately thought of the garden of forking paths.

From the paper:

Tree representation of choices to represent and test pause-periods. The ‘pause’ is defined as either no-trend or a slow-trend. The trends can be measured as ‘broken’ or ‘continuous’ trends. The data used to assess the trends can come from HadCRUT, GISTEMP, or other datasets. The bottom branch represents the use of ‘historical’ versions of the datasets as they existed, or contemporary versions providing full dataset ‘hindsight’. The colour coded circles at the bottom of the tree indicate our assessment of the level of evidence (fair, weak, little or no) for the tests undertaken for each set of choices in the tree. The ‘year’ rows are for assessments undertaken at each year in time.

Thus, descending the tree in the figure, a typical researcher makes choices (explicitly or implicitly) about how to define the ‘pause’ (no-trend or slow-trend), how to model the pause-interval (as broken or continuous trends), which (and how many) datasets to use (HadCRUT, GISTEMP, Other), and what versions to use for the data with what foresight about corrections to the data (historical, hindsight). For example, a researcher who chose to define the ‘pause’ as no-trend and selected isolated intervals to test trends (broken trends) using HadCRUT3 data would be following the left-most branches of the tree.

Actually, it’s the multiverse.