Steven Calder, Developer in Minneapolis, MN, United States
Steven is available for hire
Hire Steven

Steven Calder

Verified Expert  in Engineering

Data Visualization Developer

Location
Minneapolis, MN, United States
Toptal Member Since
November 13, 2019

Steven is a versatile data scientist who connects concepts from various fields of thought to create novel solutions and identify new areas to apply data. His work emphasizes clear communication of technical concepts via interactive visualizations and narrative storytelling, allowing decision-makers from all backgrounds to understand and take appropriate actions.

Data AnalyticsData VisualizationMachine LearningBig DataA/B TestingNatural Language Processing (NLP)PythonSQLBusiness Intelligence (BI)ETLPython 3Data PipelinesPostgreSQLPandasNumPy

Portfolio

Doximity
Python, Pandas, NumPy, A/B Testing, SciPy, Jupyter, Scikit-learn...
Siemens
Amazon Web Services (AWS), Tableau, PostgreSQL, Python, Data Analytics...
CrossEngage
R, Spark, Cassandra, PostgreSQL, Python, Data Analytics, Data Visualization...

Experience

Data Analytics - 13 yearsData Science - 13 yearsData Visualization - 13 yearsPython - 11 yearsSQL - 11 yearsPandas - 8 yearsTableau - 6 yearsTime Series Analysis - 6 years

Availability

Full-time

Preferred Environment

Tableau, Looker, Python, Snowflake, PostgreSQL, Pandas, Python 3

The most amazing...

...use of data has been to combine data from various railway sensors to create predictive maintenance products, resulting in multiple patents along the way.

Work Experience

Senior Staff | Data Science and Analytics

2019 - 2021
Doximity
  • Developed NLP models to extract features from medical literature and match the content with users.
  • Led the dimensional modeling team in structuring company-wide data.
  • Leveraged the company data to customize the product to achieve company goals.
Technologies: Python, Pandas, NumPy, A/B Testing, SciPy, Jupyter, Scikit-learn, Natural Language Toolkit (NLTK), Natural Language Processing (NLP), Generative Pre-trained Transformers (GPT), GPT, Data Visualization, Looker, Snowflake, Amazon SageMaker, Machine Learning, BERT, Word2Vec, Torch, PyTorch, Deep Learning, ETL, Dimensional Modeling, Predictive Modeling, Data Analytics, Amazon Web Services (AWS), Business Intelligence (BI), Data Analysis, Big Data, Apache Airflow, Data Pipelines, Spark, PyCharm, Data Modeling, Project Management, People Management, Dask, APIs, Clustering, Python 3, Large Language Model (LLM)

Principal Data Scientist | Head of R&D Data Analytics Center

2016 - 2019
Siemens
  • Recruited, hired, and led an international and multicultural team of 15 data experts, including some with their direct reports.
  • Organized international teams in Japan, Singapore, Hong Kong, and Europe.
  • Managed simultaneous project proposals, budgets, and timelines.
  • Developed and maintained scalable ETL systems to ingest, process, and analyze streams of petabytes of data from diverse sources.
  • Produced interactive data visualization products with real-time analytics for resource allocation, predictive maintenance, and improvements to odometric systems.
  • Authored intellectual property applications and academic publications.
Technologies: Amazon Web Services (AWS), Tableau, PostgreSQL, Python, Data Analytics, Data Visualization, Pandas, Scikit-learn, Looker, Generative Pre-trained Transformers (GPT), GPT, Natural Language Processing (NLP), SQL, Data Science, Snowflake, Time Series Analysis, NumPy, Amazon SageMaker, Torch, TensorFlow, BERT, Business Intelligence (BI), ETL, Machine Learning, Predictive Modeling, Time Series, People Management, Project Management, Big Data, Deep Learning, Data Analysis, SciPy, Redshift, Dimensional Modeling, Jupyter, Data Pipelines, pgAdmin, PyCharm, Data Modeling, Luigi, Dask, Tableau Server, APIs, Clustering, Neural Networks, Python 3, GIS

Head of Data Science

2015 - 2016
CrossEngage
  • Recruited, hired, and led a team of ten data specialists.
  • Designed an artificial intelligence technique for predicting and directing customer behavior.
  • Invented new techniques for machine learning with imbalanced datasets—expansion of the SMOTE algorithm for online marketing.
  • Presented our data products to clients and investors.
Technologies: R, Spark, Cassandra, PostgreSQL, Python, Data Analytics, Data Visualization, Pandas, Scikit-learn, Generative Pre-trained Transformers (GPT), GPT, Natural Language Processing (NLP), SQL, Data Science, Time Series Analysis, NumPy, Amazon Web Services (AWS), TensorFlow, Business Intelligence (BI), ETL, Machine Learning, Predictive Modeling, Time Series, People Management, A/B Testing, Data Analysis, SciPy, Big Data, Jupyter, Data Pipelines, PyCharm, Data Modeling, Deep Learning, Project Management, APIs, Clustering, Neural Networks, Python 3

Data Scientist

2013 - 2015
Rocket Internet
  • Consulted portfolio companies—HelloFresh, Zalando, Carmudi—to identify new opportunities to utilize their data.
  • Oversaw the construction of scalable ETL pipelines to plan for growth.
  • Created price prediction models for the global used vehicle market.
  • Worked with product owners to determine KPIs with automated reporting.
  • Segmented customers for marketing and churn prediction.
Technologies: Python, NumPy, SciPy, Machine Learning, R, PostgreSQL, Data Analysis, Data Visualization, Data Analytics, Business Intelligence (BI), ETL, Predictive Modeling, Big Data, Algorithmic Trading, Data Pipelines, PyCharm, Data Modeling, Deep Learning, Amazon Web Services (AWS), APIs, Clustering, Neural Networks, Python 3

Postdoctoral Researcher

2011 - 2013
Wageningen University & Research
  • Supervised a team of six graduate students and managed international projects with teams from Japan, Egypt, Israel, Canada, the USA, and Europe.
  • Applied machine learning to chemical systems to produce biochemical sensors.
  • Acquired and analyzed the data from "artificial noses" as a diagnostic instrument.
  • Authored research articles in top journals and reviewed articles as a peer reviewer.
Technologies: MATLAB, Python, Data Analytics, Data Visualization, SQL, Data Science, Machine Learning, Predictive Modeling, Data Analysis, Data Modeling, People Management, Python 3

Rail Vehicle Anomalies

https://tabsoft.co/2My67Lp
By examining the data from sensors on a moving train, we have identified a set of different types of anomalous readings. These types can be visualized to explain the different conditions or locations where these anomalies occur.
A dashboard presenting the findings is available on the website above.

Languages

Python, SQL, Snowflake, Python 3, R

Libraries/APIs

Pandas, NumPy, Scikit-learn, Natural Language Toolkit (NLTK), PyTorch, TensorFlow, Dask, SciPy, Luigi

Tools

Tableau, Looker, Amazon SageMaker, Apache Airflow, PyCharm, pgAdmin, MATLAB, Jupyter, GIS

Paradigms

Data Science, Business Intelligence (BI), ETL, Dimensional Modeling

Storage

PostgreSQL, Data Pipelines, Redshift, Cassandra

Other

Data Analytics, Data Visualization, BERT, Natural Language Processing (NLP), Machine Learning, Predictive Modeling, A/B Testing, Big Data, Word2Vec, Data Modeling, GPT, Generative Pre-trained Transformers (GPT), Time Series Analysis, Torch, Time Series, Deep Learning, Tableau Server, APIs, Clustering, Neural Networks, Large Language Model (LLM), Data Analysis, People Management, Algorithmic Trading

Platforms

Amazon Web Services (AWS)

Industry Expertise

Project Management

Frameworks

Spark

2008 - 2011

Ph.D. in Chemical Physics

University of Minnesota - Minneapolis, MN

2006 - 2008

Master's Degree in Chemistry

University of Minnesota - Minneapolis, MN

2003 - 2006

Bachelor's Degree in Chemical Physics

College of William and Mary - Williamsburg, VA