Collaborating Authors


The AI Index 2021 Annual Report Artificial Intelligence

Welcome to the fourth edition of the AI Index Report. This year we significantly expanded the amount of data available in the report, worked with a broader set of external organizations to calibrate our data, and deepened our connections with the Stanford Institute for Human-Centered Artificial Intelligence (HAI). The AI Index Report tracks, collates, distills, and visualizes data related to artificial intelligence. Its mission is to provide unbiased, rigorously vetted, and globally sourced data for policymakers, researchers, executives, journalists, and the general public to develop intuitions about the complex field of AI. The report aims to be the most credible and authoritative source for data and insights about AI in the world.

The 2021 AI Index: Major Growth Despite the Pandemic


This year's report shows a maturing industry, significant private investment, and rising competition between China and the U.S. The last decade was a pivotal one for the AI industry, and 2020 saw AI substantially increase its impact on the world despite the chaos brought about by the COVID pandemic: Technologists made significant strides in massive language and generative models; the United States witnessed its first drop in AI hiring ever – pointing to a maturation of the industry – while hiring around the world increased; more dollars flowed to government use of AI than ever before, while colleges and universities offered students double the AI courses from a few years ago. These are just some of the findings from the 2021 AI Index, an annual study of AI impact and progress developed by an interdisciplinary team at the Stanford Institute for Human-Centered Artificial Intelligence (HAI) in partnership with organizations from industry, academia, and government. "The impact of AI this past year was both societal and economic, driven by the increasingly rapid progress of the technology itself," said AI Index co-chair Jack Clark. "With the AI Index, we can actually measure and evaluate the changes, enabling leaders and decision makers to take meaningful action to advance AI responsibly and ethically with humans in mind." The 2021 AI Index is one of the most comprehensive reports about AI to date, analyzing and distilling patterns about AI's impact on everything from national economies to job growth to the analysis of technical progress within AI research itself, and analysis of the diversity (or lack of) among the people who create AI systems.

An Investigation of COVID-19 Spreading Factors with Explainable AI Techniques Artificial Intelligence

Since COVID-19 was first identified in December 2019, various public health interventions have been implemented across the world. As different measures are implemented at different countries at different times, we conduct an assessment of the relative effectiveness of the measures implemented in 18 countries and regions using data from 22/01/2020 to 02/04/2020. We compute the top one and two measures that are most effective for the countries and regions studied during the period. Two Explainable AI techniques, SHAP and ECPI, are used in our study; such that we construct (machine learning) models for predicting the instantaneous reproduction number ($R_t$) and use the models as surrogates to the real world and inputs that the greatest influence to our models are seen as measures that are most effective. Across-the-board, city lockdown and contact tracing are the two most effective measures. For ensuring $R_t<1$, public wearing face masks is also important. Mass testing alone is not the most effective measure although when paired with other measures, it can be effective. Warm temperature helps for reducing the transmission.