| Past data isn't limited at all. We have at least 2 centuries of rapid innovation to draw on when we note that unemployment has not skyrocketed with technological progress. Real GDP per capita has risen almost uninterrupted over the last 200 years [1], and is on the order of 20 times what it was 200 years ago. Yet, unemployment is still exceedingly low by world and historical standards. [1] http://www.acus.org/files/u3/USA-GDP-1810-2010.png The market works to provide jobs to those who demand jobs. Shifts in technology are not discrete jumps, but continual trends that price mechanisms can smoothly correct for. >assembly lines needed a large amount of labor The reason that assembly lines became so useful was that they needed substantially less labor per product, and could produce products far more cheaply. What you're missing is that the reason that people were still employed at relatively similar levels and GDP per capitas was because consumer demand rose to meet lower prices. These are all matters of supply and demand. > the currently in-progress one, of moving from industrial employment to service-sector and/or information-sector employment This shift is already very much completed. Over 80% of the USA's economy is service-sector at this point, and we haven't observed any unemployment issues that can be attributed to technology growth. What we can predict about the future is what our modern understanding of economics and historical perspectives tell us. As long as there is demand for jobs in a market economy, there will be jobs. |
In this case the relevant event is sector-wide shifts in employment, of the farms->factories variety. We have very little data on those, because they occur once or perhaps twice in our data set. So we can't really generalize with any confidence about them: which features of that particular transition are general features of a sector-to-sector transition, and which ones depend on idiosyncracies of farms or factories or the particular time? Will factories->X look the same as farms->factories? We do have somewhat better data on which depend on idiosyncracies of place, since you can look at the industrial revolution in the U.S. versus in the UK or Germany or Japan (though those aren't independent data sets).
We have a lot of data in raw terms, but I think of that as just having data on a small number of macro-scale events, but at high resolution (monthly or better for many years). Now if we had observed 4 or 5 such macro-scale shifts (at least), that's the kind of data that would be needed to build a good model of how such transitions work. So I don't think we can say with much confidence, certainly not statistically valid confidence, how market mechanisms handle such shifts. What we have very good data on is how market mechanisms work in the "normal" case, within a largely stable paradigm. But for farm->factory type transitions, we have basically small-N case studies that people are trying to extrapolate from. The "market will sort it out—it always does" view is certainly one possible extrapolation, but I don't think the evidence confirming it is very strong.