Jihar Gifari
Jihar Gifari, smiling, in a navy suit and glasses

Jihar Gifari, Senior Applied Data Scientist, London.

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Results

  1. 01

    £80K+

    Incremental revenue identified

    A marketing mix model for Sigma Sports moved budget between channels. No extra spend, Q4 2025.

    Sigma Sports · Marketing mix modelling

  2. 02

    €176K+

    Win-back uplift in backtests

    Churn and lifetime value models turned Penhaligon's (PUIG) CRM from fixed rules to value-based targeting.

    Penhaligon's (PUIG) · Churn and lifetime value

  3. 03

    15%

    Better customer retention

    A churn prediction system used by finance and marketing at Shopee International Indonesia.

    Shopee · Churn prediction

  4. 04

    50%

    Lower production cost

    An AI image scoring system for cottages.com that also added 4% bookings on the weakest 20% of listings.

    cottages.com · Computer vision

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anything.

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Hiring? Check a job description against my experience, gaps included.

Work

6+ years of models that had to pay their way.

Open a role to see the projects inside it, then open a project to watch how it works.

6 roles · 11 projects

  1. Marketing measurement and customer models for AskBosco's clients, built into the company's analytics platform.

  2. AI products for FRAME's clients, from computer vision to finance automation.

    Also in this role

    • Assisted on an AI course: supported students with coding challenges and taught Python sessions

  3. An AI assistant for Umrah pilgrims: 1st place in an international competition, then the MSc dissertation.

  4. Production ML for growth and retention on Southeast Asia's largest e-commerce platform, with BI analysts and business teams.

    Also in this role

    • Scaled the data science team from 2 to 5 as second-in-command, mentoring junior data scientists in Python, feature engineering and stakeholder communication
    • Deployed models into production with BI engineers, and supported growth work with data products and analysis

  5. Analytics and product work for an Indonesian securities firm's trading apps.

    Also in this role

    • Data analysis behind a personalised, data-driven marketing strategy
    • Improved customer analytics dashboards in Tableau
    • Earlier, in 2019: research, business development and sales internships at the same firm

  6. Six years of teaching data science: 300+ students, 1,500+ hours, and a published book.

    Jihar teaching a machine learning class at Indonesia's Ministry of Finance
    Teaching machine learning with Python at Indonesia's Ministry of Finance, 2020

    What it involved

    • Shift Academy, Oct 2020 to Oct 2021: data science courses for individual and corporate clients
    • Wrote the course book, Learning Modules: Data Science and Machine Learning (Inspira, 2021, ISBN 978-623-7178-43-9)
    • DQLab, Aug 2020 to Mar 2021: daily articles for the DQLab blog, which grew the site's traffic by 31%
    • Scientify Education: founder and lead instructor, 300+ students and 1,500+ teaching hours
    • Taught machine learning with Python at Indonesia's Ministry of Finance in 2020

In their words

  • “He was instrumental in the delivery of several high-value machine learning projects.”

    Gordon SquireLead Data Scientist at AskBosco. Managed Jihar directly.
    Read the full recommendation

    I had the pleasure of managing Jihar, he proved himself to be a very intelligent, capable and enterprising data scientist. He was instrumental in the delivery of several high-value machine learning projects. Notably, he successfully developed and productionised bespoke predictive models for a major multinational luxury retail client, driving demonstrable business value for their marketing team. His ability to plan and structure technical work with a focus on results was particularly beneficial. I can recommend him to any organisation.

  • “Jihar has very good and deep understanding in data science.”

    Gayus YonathanData Scientist at Shopee. Managed Jihar directly.
    Read the full recommendation

    Jihar has very good and deep understanding in data science. In shopee, he has contributed much in terms translating business problem and come out with technical solutions. He has good grasp of business acumen as well. I commend Jihar for his skills and knowledge. Jihar also has left us with his legacy of python module.

  • “People come and go everyday but a few of them leave their marks. Jihar is one of them.”

    Cattleya Trienanda PutriHead of Digital Business at IFG (Indonesia Financial Group). Managed Jihar directly.
    Read the full recommendation

    People come and go everyday but a few of them leave their marks. Jihar is one of them. I met him as an internship in my current company. After two years, I need someone with good working personality. Then my first name that comes up was him.

    Jihar is someone who you can actually talked to and discussed with various topics. His ability to understand big picture by linking the small dots is outstanding. For his particular skill as Data Analyst in my company is remarkable, I havent thought that this is very important until he showed it to me and implement it directly to the business.

    He is a very a good member in the team. Jihar is very profound person, his ability to tackle a problem is remarkable. Yes, with small warm smile. He earns my highest recommendation.

  • “Jihar is a very good tutor.”

    Raihan FirdausSenior Revenue Operations at Intellect. Was Jihar's client.
    Read the full recommendation

    Jihar is a very good tutor. He has a deep understanding in data field, both in fundamental and technical aspect which demonstrated in the way he teach and explain class's material, as well as answering questions from the class attendee (including myself). He is obviously one of the most outstanding data professional that i know. Really looking forward to work with him, hope one day there will be our cross path.

Education, recognition and tools

Education

  • MSc Data Science · Distinction

    Leeds Beckett University, UK, 2024

    Dissertation: an AI-powered Umrah assistant combining fine-tuning, prompt engineering and corrective RAG with real-time web scraping. Marked distinction without revision.

  • Bachelor of Economics · Cum laude, 3.60 of 4.00

    Brawijaya University, Indonesia, 2020

    Finished early, in 3.5 years. Thesis: the effect of Islamic holidays on abnormal returns of sectoral stock indices in Indonesia.

Recognition

  • 1st place, international AI competition

    Ministry of Hajj and Umrah, Saudi Arabia, 2024

  • 3rd place, national economics debate

    Indonesia, 2018

  • Best freshman student (TRANSFORMAN), economics

    Brawijaya University, 2016

  • Valedictorian

    High school, Indonesia, 2016

Writing and training

  • Learning Modules: Data Science and Machine Learning

    Inspira, ISBN 978-623-7178-43-9, 2021

  • The Influence of Islamic Holidays on Sectoral Stock Index Abnormal Returns in Indonesia

    Jurnal Ilmiah Mahasiswa FEB (JIMFEB) 9(1), 96 to 105, 2020

  • Problem solving, lean thinking and effective communication

    Shopee International Indonesia, 2022

  • Data science and machine learning

    Purwadhika Digital School, 2020

Tools, by how deep they go.

Languages: English (IELTS 7.0), Bahasa Indonesia (Native)

Lead end to end
Python, SQL, XGBoost, LightGBM, scikit-learn, Survival models, Regression, Classification, Pandas, Feature engineering, Customer analytics, ETL, Tableau, Matplotlib, Plotly, Streamlit, Marketing mix modelling, Churn prediction, Customer lifetime value, Customer segmentation, Forecasting, Recommendation systems, BigQuery, PostgreSQL.
Deliver independently
OpenAI API, Fine-tuning, RAG, Prompt engineering, Embeddings, Git, Modular architecture, API design, Reproducible pipelines, GCP, Vertex AI, GCS, Automated pipelines, Model monitoring.
Working knowledge
Docker, FastAPI, REST APIs, OpenAPI, Pytest, Mypy, Ruff, CI/CD, Auth0, JWT.

Hiring for marketing measurement or customer ML in the UK?

Eligible to work in the UK, no sponsorship needed. Based in London.

Email me Download CV (PDF)LinkedInGitHub

The CV is a two-page PDF, rebuilt from this site whenever it changes.

Jihar Gifari · London · jigifari@gmail.com · +44 7985 687426