---

I am a postdoctoral researcher in Environmental Statistics from Department of Environmental Science, Policy and Management at University of California, Berkeley, co-supervised by Dr. Timothy M Bowles and Dr. Perry de Valpine. My research aims to develop a spatial-temporal model that links cropping system diversification with crop yields during extreme weather and use Bayesian causal inference to explore how the key factors of interest, such as soil health or precipitation, affect the crop yield using extensive observational data. Before joining UC Berkeley, I obtained my Ph.D. degree in statistics from the Department of Statistics at University of California, Santa Cruz, where I work with Dr. Robert Lund in developing novel models to accommodate count time series, censored time series, and periodic time series. My work produces applied statistical and machine learning models to deliver projects in climatology, astronomy, and object tracking. My professional goal lies with bridging the gap between interpretable time series models and industrial applications by using probabilistic programming and cloud technologies.

I holds a Master’s degree in Mathematics from CSU Northridge in 2016 and B.S. in Economics from Guangdong, China in 2009. I am a member of American Statistics Association and American Mathematical Society. 

Working Paper

Jiajie Kong, Robert Lund and Jon Woody (2023+), Partical Filtering Method for Generalized Censored Time Series, (for Journal of the American Statistical Association)

Stefanos Kechagias, Jiajie Kong, James Livsey and Robert Lund (2023+), An R Package for Count Time Series with Specified Marginal Distributions, (for Journal of Statistical Software)

Submitted Papers

Jiajie Kong and Robert Lund (2023), Poisson Count Time Series, (Submitted to Journal of Time Series Analysis)

Jiajie Kong, Tony Pourmohamad and Herbie Lee (2023), An Acquisition Function Family for Bayesian Optimization. (Submitted to Operations Research Forum)

John Grant, Jiajie Kong, Xin Liu, Robert Lund and Jon Woody (2023), Lindley Processes with Correlated Changes. (Under major revision for Journal for Statistical Computation and Simulation)

Publications

Yisu Jia, Robert Lund, Jiajie Kong, Jamie Dyer, Jon Woody and Steve Marron (2023), Trends in Northern Hemispheric Snow Presence. Journal of Hydrometeorology, Vol 24, pp. 1137-1154.

Jiajie Kong and Robert Lund (2021), Seasonal Count Time Series, Journal of Time Series Analysis, Vol 44, pp. 93-124.

Majid Mojirsheibani and Jiajie Kong (2016), An Asymptotically Optimal Kernel Combined Classifier, Statistics and Probability Letters, Vol 119, pp. 91-100.

TA Experience

• STAT 5 Statistics Fall 2017, Winter 2018, Spring 2020, and Summer 2020
• STAT 7 Statistical Methods for the Biological, Environmental, and Health Sciences Laboratory Winter 2019, Spring 2019, Summer 2019, Winter 2020, Fall 2020, and Winter 2021
• STAT 80A Game Theory Fall 2018, Fall 2019
• STAT 131 Introduction to Probability Summer 2018, Spring 2021, and Fall 2021

Hobbies

I enjoy hiking, bicycling, traveling, cooking, and listening to jazz and metal music. I am an amateur photographer and an avid novice user of Emacs and Org mode.