DIY Bertin Matrix with 569 Dominoes and No Glue

The footnotes lead to some fascinating context into the associated research field.

The World Values Survey, which started in 1981, is "the largest non-commercial, cross-national, time series investigation of human beliefs and values ever executed, currently including interviews with almost 400,000 respondents. Moreover the WVS is the only academic study covering the full range of global variations, from very poor to very rich countries, in all of the world’s major cultural zones".

"WVS consists of nationally representative surveys conducted in almost 100 countries which contain almost 90 percent of the world’s population, using a common questionnaire" .

Their latest research study examines "Values In a Time Of Crisis" & the effects of the Covid-19 pandemic on values.

"a natural experiment indeed—to study how people’s moral values behave during times of crises. In the face of lacking evidence, we cannot take it for granted that the glacial stability of values observed in normal times continues throughout the Corona crisis. This uncertainty opens new territory and raises several imminent research questions:

  - Does the Corona pandemic impact on people’s values? In other words, do people change their values under the imprint of this crisis? 

 - If yes, how massive are these changes? And if these changes are massive, in what direction do they move? 

 - How enduring are these changes, once an end of the crisis is at sight and once its economic consequences are overcome: do people’s moral values revert back to their old setpoint or does the crisis leave a lasting impact?"

http://www.worldvaluessurvey.org/WVSEventsShow.jsp?ID=416

This optimization problem is very similar to that of minimizing the diagonal bandwidth of a matrix, a common problem in large numerical computations [1]. It is also related to cluster finding in graphs and graph layouts by considering the adjacency matrix.

The difference is that in both those cases the values are boolean, but in this post the cost function is weighted.

[1] https://en.wikipedia.org/wiki/Cuthill%E2%80%93McKee_algorith...

I'm a mediocre woodworker, but it seems to me cutting the dominoes on a table saw would be faster than laser cutting. Setup a sled with a stop of the proper width to create strips. The strips could be run through using the sled with the stop set to a potentially different dimension. One can then use either a drill press or a hand drill with a template to guide hole placement. A drill press would be preferred, since getting exact placement and alignment is essential to getting the rods to work.

I love the physical modelling and manipulation; but there has to be a better way than removing and replacing all those rods every time you want to switch dimensions, surely?

What a neat way of thinking about (dimension a, dimension b, value) tuples.

Does anyone know of any library to visualise data this way?

Is the reordering NP complete?