Which hypothesis test should I use? A decision flow for business questions
Oct 6, 2026
Senior data scientist · R/Shiny engineer · PhD in Finance
Hi, I’m Wlademir.
I lead an R/Shiny engineering team and have spent the last decade building data applications that make it to production. I write here about what I learn on the way: analyses with code you can run, the engineering around data products, and notes on building a career in data.
What you will find here
Applied data science
Analyses that start from a real question and end with a decision. Finance, customer behavior and visualization, with the code included.
Data applications in production
Shiny, Quarto, deployment and the less glamorous work that turns a script into something people rely on.
Career in data
What I have learned working with data across companies and roles, from analyst to building and leading data products.
Latest articles
No matching items
The book
O Manual do Cientista de Dados
O Manual do Cientista de Dados
A free, open handbook in Portuguese about data science in practice: statistics, modeling, visualization and the reasoning behind them. An ongoing project, written in Quarto and open to contributions.
Research
Before industry, I did academic research in behavioral finance at UFSC, mostly on how investors decide under risk. These are the papers I would point you to first.
Journal of Behavioral and Experimental Finance · 2018 On the neural substrates of the disposition effect and return performance
Managerial and Decision Economics · 2017 Risk aversion, the disposition effect, and group decision making: an experimental analysis
PLoS ONE · 2019 Propensity to sell stocks in an artificial stock market
Revista Brasileira de Economia · 2019 Efeito disposição: propensão à venda de investidores individuais e institucionais