English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

In this research we study productivity trends of hybrid corn - an importantsubdomain of food production. We estimate the yearly rate of yield improvementof hybrid corn (measured as bushel per acre) by using both information onyields contained in US patent documents for patented hybrid corn varieties andon field-test data of several hybrid corn varieties performed at US Statelevel. We have used a generalization of Moore's law to fit productivity trendsand obtain the performance improvement rate by analyzing time series of hybridcorn performance for a period covering the last thirty years. The linearregressions results obtained from different data sources indicate that theestimated improvement rates per year are between 1.2 and 2.4 percent. Inparticular, using yields reported in a sample of patents filed between 1985 and2010, we estimated an improvement rate of 0.015 (R2 = 0.74, Pvalue = 1.37 x10^-8). Moreover, we apply two predicting models developed by Benson and Magee(2015) and Triulzi and Magee (2016) that only use patent metadata to estimatethe rate of improvement. We compare these predicted values to the rateestimated using US States field-test data. We find that, due to a turning pointin patenting practices which begun in 2008, only the predicted rate (rate =0.015) using patents filed before 2008 is consistent with the empirical rate.Finally, we also investigate at the micro level - on the basis of 70 patents(granted between 1986 and 2015) - whether the number of citations received by apatent is correlated with performance achieved by the patented variety. We findthat the relative performance (yield ratio) of the patented seed is positivelycorrelated with the total number of citations received by the patent (untilDecember 2015) but not the citations received within 3 years after the grantedyear, with the patent application year used as control variable.

Food Productivity Trends from Hybrid Corn: Statistical Analysis of Patents and Field-test data