Nick Chaiyachakorn, biostatistician

(MS, MSW, if it matters...)
nchaiyachakorn@gmail.com / chaiyach@ohsu.edu
GitHub (not that there's much...)
Portland, OR
RI-CLPM path diagram
Path diagram for the random-intercept cross-lagged panel model
Causal diagram for Lord's paradox
Causal diagram behind Lord's paradox, revisited

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Welcome to my professional website, focusing on Nick as a statistician.

I am an applied statistician with an MS in Biostatistics with, with experience in the applied health and social sciences – until now mostly in academic institutions. I enjoy working in multidisciplinary teams. I've worked in all sorts of fields – everything from mental health epidemiology, autism services research, large-scale opinion survey research, spatiotemporal modelling and geography in public health...

I believe my best work has always been done in collaboration with methodologists from other fields. Although I'm trained as a biostatistician, I've enjoyed working with methodologists that have been industrial/organizational psychologists, geographers, research/evaluation folks in health departments, etc...

I care both about analysis and rigorous research design. I gravitate towards observational/longitudinal research with large and complex samples, and techniques that answer causal questions. Currently, my favorite tools are structural equation models with mixed-effects bells and whistles.

Finally, I believe everybody counts.

I am looking for a job! Email me at nchaiyachakorn@gmail.com if my statistical toolkit's right up your alley

Professional history


2026, summer.

It was a privilege to be an HRTP intern at New York City's Department of Health and Mental Hygiene. (I think it used to stand for Health Research Training Program (?)) I worked with the Bureau of Mental Hygiene's Surveillance team, wrangling data from many meaningful, very large real-life public health datasets — anonymized patient discharges (for those in the know, NYS SPARCS), ED admissions data, referrals to mental health services. I ended up creating an interactive composite indicator dashboard with R and Shiny – with maps, a sensitivity analysis tool, etc... And, I met fantastic people who taught me a great deal about work-life balance... so you can be in there for the long haul.


2024-2026.

I finally decided to get an MS in Biostatistics from Oregon Health and Science University's School of Public Health. What a privilege to finally get a well-rounded statistical training... from causal methods with epidemiologists, to clinical trial design with cancer biostatisticians (alpha-spending! adaptive methods!)

More importantly, I spent two wonderful years interning in an NIH-funded research trainee program for pre-doctoral students, learning how to conceive and plan secondary data analysis on Medicaid claims (for those in the know, CMS' T-MSIS TAF), looking at what might be associated with ED use by autistic adolescents in crisis... and comparing state rates. I learned a great deal about secondary data analysis on large health datasets - operationalizing analytic cohorts, sets of diagnosis and CPT codes...

I had some fun (but sadly unfinished) side-tracks doing geographical analyses on provider availability by geography (NPI databases, the "AHRF Health Resource File"), and cutting my teeth on GIS by measuring overlaps between Census-designated Native American tribal areas, and Census estimates of actual Native American populations.


2021-2024.

I picked up an MSW from Portland State University. Why? I thought you were a statistician, Nick? Well, I wanted to learn and do systems-level social work. Most importantly, it let me take advanced quantitative methods classes at PSU's Psychology department e.g. structural equation modelling, multilevel modelling! And, it opened a door or two:

For two wild years, and for some hands-on real-world policy experience, I interned at Multnomah County's Joint Office of Homeless Services. I did various analytic, planning, and evaluation-adjacent things for Adult Coordinated Access, the Data Team, and the Supportive Housing Services oversight team. And I served under three chief honchos!

I also spent a summer as an Oregon Summer Fellow at the Oregon Health Authority's Health Policy and Analytics unit, analyzing Oregon managed Medicaid "health-related services" payments, with the help of a kind RA from ORPRN (Oregon Rural Practice-Based Research Network). I piloted health disparity analyses in spending. It was fun.


2016-2020.

I had tremendous fun getting a BA in Mathematics from Reed College. I wanted to be an algebraic topologist - but also cared deeply about inclusion in the mathematics community. The highlight of my undergrad experience was participating in J.P. May's UChicago REU (2018).


Data/stats/programming writeups


Recreational programming: a highly portable C89 RISC-V emulator.

In my spare time, I am writing a highly portable riscv64 emulator. By "highly portable", it is (a) written in C89 with a user-defined 64-bit "long long" datatype, (b) is endian-independent – e.g. M68K is big-endian! – and (c) runs on computers with very small memory capacities by "meta-paging" emulated physical RAM to and from disk.

Non-goal: an emulator fast enough for interactive access! Being able to submit batch jobs is enough.

The target emulated environment is a ~8GB Linux environment with multiple serial TTYs, block disk access, etc.

The target host is an MMU-less 68k Macintosh with 8-16MB memory, but with a multi-GB disk

The target use case: running batch jobs, e.g. cross-compiling in the emulator for the host.

Design for a memory access tracing format that can record ~30 seconds of a ~1 GHz emulated machine (2026-10-14). Recordings of memory access patterns from a booting Linux VM will be used to determine which is the most efficient combination of "meta-page" size, and number of meta-pages resident in memory.


Send a file to me via age encryption
# created: 2026-09-29T07:05:23-07:00
# public key: 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