A guide to how how innovation has changed over time
This post provides a quick overview of claim articles in New Things Under the Sun related to how innovation has changed over time.
Can’t find what you’re looking for? The easiest thing is to just ask me: I’m happy to point you to the best article, if there is a relevant one.
Science is getting harder
Innovation (mostly) gets harder
Is technological progress slowing? The case of American agriculture
Are ideas getting harder to find because of the burden of knowledge?
The decline in writing about progress
Progress in the film industry
Gender and what gets researched
Increasingly distant knowledge spillovers
Twitter and the spread of academic knowledge
What if we could automate innovation?
When technology goes bad
Examines a range of different lines of evidence to argue that the “size” of the typical scientific discovery may be getting smaller. Evidence is drawn from:
Nobel prizes
Top cited papers
Measures of disruption
Linguistic measures
Citations to recent work
While each argument has holes, I argue they’re not the same holes. Stack them up and you begin to get something that holds water.
Examines different lines of evidence to argue that the amount of effort needed to improve a technology by a proportional amount tends to increase over time. Evidence is drawn from:
Moore’s law
Agriculture
Machine learning
Health
Patents
Firm-level data
National statistics
Some objections are also considered, but ultimately rejected
Are these data series are focusing on the wrong things?
Perhaps technological shouldn’t be proportional, but merely linear?
American agriculture has experienced a slowdown in technological progress, defined as the efficiency of transforming inputs such as labor and land into outputs, like corn.
This slowdown is reflected in the decline of the 20-year growth rate of yields and total factor productivity (TFP).
Some potential confounders, such as the impact of changing weather and rising CO2 levels on TFP growth appears to be limited but may pose a challenge in the future.
The article attributes the slowdown in technological progress in American agriculture is attributed to the stagnant level of R&D from 1980 to 2007 and the slow diffusion of innovations into agriculture, from a US economy that may also be experiencing a slowdown.
Perhaps innovation is getting harder because of the burden of knowledge: the idea that pushing the knowledge frontier requires progressively more knowledge as fields mature.
Evidence for the burden of knowledge shows up in a few places:
The age at which people achieve certain innovation milestones is rising
More and more innovation is conducted by larger and larger teams
People are specializing more and more
One study looked at what happened to mathematics when the USSR collapsed and in the West, different areas of math suddenly got different infusions of knowledge. The ones with a higher subsequent burden of knowledge ended up with bigger teams and more specialization.
A study of English texts from 1500-1900 shows an increase in progress-oriented language leading up to the Industrial Revolution
This is consistent with theories of the industrial revolution that argue changes in cultural attitudes towards progress were an important factor
Recent analysis reveals a decline in progress-related words across since the 1950s across several languages and text datasets
English fiction has shown a longer run decline in its use of progress related words
Critically acclaimed literature shows increasing focus on the past, while bestsellers maintain more interest in the present and new technologies
Despite the common perception that the movie industry is suffering from an age of decadence, the quality of movies may be increasing.
Review aggregators such as Rotten Tomatoes and Metacritic show a steady upward trend in the quality of the best rated movies.
The number of new US-origin movies listed on IMDb has also increased dramatically in the digital era
This increase is primarily due to the increase in production from independent studios (major studios have reduced their output).
The dominance of repetitive franchises can be explained by the distinction between the behavior of major and independent studios, with the major studies focusing on making fewer movies that appeal a bit to everyone, rather than movies that appeal a lot to a small audience.
Scientists and inventors may be influenced by their personal experiences in deciding what to work on, including their gender (though gender may also matter for other reasons).
Patents developed by a majority of male inventors are more likely to relate to male-focused topics and patents developed by a majority of female inventors are more likely to relate to female-focused topics. This pattern is also seen in the products developed by startups with female founders.
Research articles with more women as authors are more likely to focus on female-related topics in biomedical research, and papers with more women coauthors are also more likely to include gender and sex analysis. In the field of history, research articles with women as authors have also tended to focus on different topics than papers by men.
There is evidence that increasing representation of women in science leads to a shift in research priorities, potentially due to increased awareness and empathy among male scientists or a mainstreaming of ideas and perspectives of women.
An increase in representation of women at all-male universities led to an increase in research related to gender, potentially due to increased hiring of women faculty and changes in research preferences of pre-existing faculty.
The idea that innovators in big cities have better access to knowledge and ideas due to their proximity to more people is called "local knowledge spillovers".
Recent studies have cast doubt on the continued strength of this concept.
One study found that the probability of a local patent citing another local patent has declined, while another found that the advantage of big cities in generating novel technology combinations has also declined.
Other studies have found that big cities are no longer using younger, more novel ideas as much as they used to.
Overall, the evidence suggests that the advantage of big cities in innovation has been declining.
Twitter is a potential platform for serendipitous discovery of academic knowledge across disciplines.
If this is the case, papers that get more tweeted about should receive more citations
Observational studies show correlation between tweets and citations, but randomized controlled trials (RCTs) yield mixed results.
Most RCTs find small positive effects (10-16% more citations) for tweeted papers, but these are often not statistically significant.
Twitter's impact may be stronger for lesser-known papers or those from lower-impact journals.
Weak evidence suggests tweeting about job market papers might slightly improve job market outcomes for economics PhD candidates.
We have a subdiscipline of economics devoted to writing down mathematical models of economic growth. What do those models say happens if the inventing can be automated?
Explains a simplified version of one popular model, where supplying a given amount of inventor-hours leads to innovation, and the amount of inventor-hours needed goes up over time.
If only people can innovate, then the rate of innovation is determined by the population growth rate.
If robots can do the inventing, the rate of innovation accelerates continually!
If robots can do some but not all of the tasks needed to innovate, the rate of innovation is determined by the population growth rate and the rate at which robots learn to do new tasks.
Discusses which assumptions in this simple model are important to get the key results and which ones can be relaxed without affecting the results
There are reasons to think future technologies may not have a benefit-cost ratio as high as in the past.
Models of economic growth where innovation sometimes results in death show that if the preference for more material goods is not too high, people may choose to stop growth when they are sufficiently wealthy.
In models where inventors can pursue safety-enhancing innovations, richer societies may increasingly focus on this kind of innovation, slowing conventional growth. There is some evidence rich countries are indeed making this decision.
Other models point out this doesn’t imply richer societies are safer, if technological progress also imposes danger.
Climate change illustrates many of these issues in a concrete way.