Darjeeling shortage

When looking for Darjeeling tea in the recent days, I found out that the summer (or second flush) harvest has been very limited due to a 104 day strike in the region linked with the call for the creation of a Gorkhaland state and the separation from West Bengal. I remember discussing the issue last year in Darjeeling, with guides and taxi drivers, who were calling for the recognition of their cultural specificities, including the use of Nepali in local schools rather than Bengali. What amazes me a lot in this strike is the engagement of the tea garden workers, who have certainly few alternatives if any in terms of income sources. Unless I misread the situation and they were barred from attending the gardens… (Of lesser concern is the rise of the tea prices by a factor of ten for the highest quality leaves.) Hopefully, the tea gardens will recover from being left to grow wild for such a long while. And from workers leaving the region to find work elsewhere.

 

only in India… [jatp]

Last time I visited India, I highlighted an advertisement for a machine-learning match-making system. This time, while eating a last aloo paratha for breakfast in Kolkata, I noticed ads for Hindu temples on the back of my Air India boarding passes which are actually run by the State of Gujarat rather than the temples themselves. (Gujarat is India’s westernmost state.)

in the bus [jatp]

on confidence distributions

As Regina Liu gave her talk at ISI this morning on fusion learning and confidence distributions, this led me to think anew about this strange notion of confidence distributions, building a distribution on the parameter space without a prior to go with it, implicitly or explicitly, and vaguely differing from fiducial inference. (As an aside, the Wikipedia page on confidence distributions is rather heavily supporting the concept and was primarily written by someone from Rutgers, where the modern version was developed. [And as an aside inside the aside, Schweder and Hjort’s book is sitting in my office, waiting for me!])

Recall that a confidence distribution is a sample dependent distribution on the parameter space, which is uniform U(0,1) [in the sample] at the “true” value of the parameter. Used thereafter as a posterior distribution. (Again, almost always without a prior to go with it. Which is an incoherence from a probabilistic perspective. not mentioning the issue of operating without a pre-defined dominating measure. This measure issue is truly bothering me!) This seems to include fiducial distributions based on a pivot, unless I am confused. As noted in the review by Nadarajah et al. Moreover, the concept of creating a pseudo-posterior out of an existing (frequentist) confidence interval procedure to create a new (frequentist) procedure does not carry an additional validation per se, as it clearly depends on the choice of the initialising procedure. (Not even mentioning the lack of invariance and the intricacy of multidimensional extensions.)

morning devotions at Dakshineswar [jatp]

Better together in Kolkata [slides]

Here are the slides of the talk on modularisation I am giving today at the PC Mahalanobis 125 Conference in Kolkata, mostly borrowed from Pierre’s talk at O’Bayes 2018 last month:

[which made me realise Slideshare has discontinued the option to update one’s presentation, forcing users to create a new presentation for each update!] Incidentally, the amphitheatre at ISI is located right on top of a geological exhibit room with a reconstituted Barapasaurus tagorei so I will figuratively ride a dinosaur during my talk!

Mahalanobis at the bus-stop [jatp]

Two bus-stops around the Indian Statistical Institute, featuring its founder, Prasanta Chandra Mahalanobis.