Sign In

Arun Subramanian

Analytics & Insights @ Amazon Ads, Ex-Nielsen, Ex-Mu Sigma

Arun Subramanian is an accomplished Analytics & Management Consultant with over 11 years of experience in the retail, clothing retail, pharma and telecommunications sectors. He has expertise in store operations, merchandising, customer insights, and marketing. Arun has an impressive educational background, having studied a Master of Manufacturing Systems Engineering and a Bachelor's degree in Chemical Engineering.

Through his roles as Director and previously Senior Manager of Marketing Effectiveness at Nielsen Marketing ROI, Engagement Manager and Associate at Mu Sigma Inc., Manufacturing Validation Coop at Biogen Idec, and Junior Manager at Dr. Reddy's Laboratories, Arun has developed a multitude of skills. His areas of expertise include sales and traffic forecasting, customer satisfaction score reporting, market basket analytics, customer profiling, personalized targeting, and much more.

Arun has a friendly and professional tone, with a focus on optimizing for SEO and including keywords and searchable phrases. He is an individual with extensive knowledge and skills, and his experience and education make him an excellent addition to any professional team.

Highlights

Aug 26 · linkedin

𝐁𝐞𝐲𝐨𝐧𝐝 𝐌𝐨𝐝𝐞𝐥 𝐕𝐚𝐥𝐢𝐝𝐚𝐭𝐢𝐨𝐧: 𝐈𝐦𝐩𝐨𝐫𝐭𝐚𝐧𝐜𝐞 𝐨𝐟 𝐁𝐮𝐬𝐢𝐧𝐞𝐬𝐬 𝐔𝐧𝐝𝐞𝐫𝐬𝐭𝐚𝐧𝐝𝐢𝐧𝐠

In data science, we often find ourselves immersed in the intricacies of model validation, like assessing accuracy metrics (e.g. RSQ, Adjusted RSQ) , goodness of fit (e.g. MAPE, RMSE), determining train-test split (e.g. 70-30 split, k-fold cross validation), and selecting an appropriate holdout approach (e.g., time based holdout, random sample holdout). While these are essential components of model development, they often overshadow a fundamental aspect: 𝒎𝒐𝒅𝒆𝒍 𝒔𝒑𝒆𝒄𝒊𝒇𝒊𝒄𝒂𝒕𝒊𝒐𝒏.

𝐀 𝐰𝐞𝐥𝐥-𝐬𝐩𝐞𝐜𝐢𝐟𝐢𝐞𝐝 𝐦𝐨𝐝𝐞𝐥 𝐢𝐬 𝐭𝐡𝐞 𝐟𝐨𝐮𝐧𝐝𝐚𝐭𝐢𝐨𝐧 𝐨𝐟 𝐚𝐜𝐜𝐮𝐫𝐚𝐭𝐞 𝐚𝐧𝐝 𝐚𝐜𝐭𝐢𝐨𝐧𝐚𝐛𝐥𝐞 𝐢𝐧𝐬𝐢𝐠𝐡𝐭𝐬. The choice of variables, their interactions, and the overall structure of the model directly influence its predictive power. Yet, this often overlooked step is where the true value of business understanding lies. Here are few real-world examples from my MMM consulting experience.

𝑨𝒑𝒑𝒂𝒓𝒆𝒍: When modeling apparel sales, understanding the nuances of product categories is paramount. Tops and bottoms, while both clothing products, have distinct seasonal patterns and purchasing behaviors. Likewise, Women's apparel demand is more susceptible to fashion and seasonal trends while its impact on Men's apparel is more subtle. And a single apparel product (e.g. jeans) can have different sizes, color, fit, etc. 𝑹𝒆𝒕𝒂𝒊𝒍: The demand patterns for products like sunscreen and toothpaste, beer and milk, turkey and chicken varies significantly. Combining these products into a single model could lead to inaccurate predictions. A more effective approach would be to segment products based on their seasonal patterns and purchasing habits. 𝑻𝒆𝒄𝒉𝒏𝒐𝒍𝒐𝒈𝒚: The technology industry is characterized by rapid innovation and evolving consumer preferences. A model that treats laptops (positive industry trend) and printers (declining industry trend) as similar products might miss critical trends. Likewise, you should differentiate between in-store vs online sales channels, inbound vs outbound marketing channels, B2C vs B2B business models. Understanding the distinct market dynamics of these categories is essential for accurate prediction.

In conclusion, while model validation is crucial, it's equally important to invest time in understanding the underlying business. Without a well specified model, you risk spending a lot of time refining and improving your models. By carefully considering the nuances of your industry, products, and customers, you can develop models that are not only statistically sound but also provide actionable insights.

#datascience #firstprinciplesthinking #modeldevelopment #businessunderstanding #modelvalidation #MMM #marketingmixmodeling #analytics #datadrivendecisions

Aug 17 · linkedin

𝐁𝐢𝐚𝐬-𝐕𝐚𝐫𝐢𝐚𝐧𝐜𝐞 𝐓𝐫𝐚𝐝𝐞𝐨𝐟𝐟 𝐢𝐧 𝐌𝐚𝐜𝐡𝐢𝐧𝐞 𝐋𝐞𝐚𝐫𝐧𝐢𝐧𝐠 𝐯𝐞𝐫𝐬𝐮𝐬 𝐂𝐚𝐮𝐬𝐚𝐥 𝐈𝐧𝐟𝐞𝐫𝐞𝐧𝐜𝐞

In traditional machine learning setup, we always focus on the bias-variance tradeoff. If you have very low bias (less assumptions, more predictors), you will end up increasing the variance and hence overfitting the data. However, if you have very high bias (more assumptions, less predictors), you will end up underfitting the data, not being able to capture the complexity. Therefore, we use goodness of fit metrics (MAPE, MSE, RMSE, etc.) along with out of sample validation to ensure model robustness.

Now, if I think about Causal Inference problems, we are focused on making very strong assumptions to capture our domain expertise in the form of causal diagrams. Here we do not focus much on bias-variance tradeoff, instead we want to be right on the variables and relationship between those variables. Hence, it requires a different approach to model validation compared to traditional ML techniques.

This distinction is very interesting in the context of Marketing Mix Modeling (MMM), which seeks to balance predictive accuracy with causal attribution. Regression is the foundation of MMM models but in terms of outcome, we are more interested in causal attribution rather than prediction. In such a scenario, shouldn't MMM models focus on more than goodness of fit metrics and out of sample validation?

Have you seen MMM models validated via techniques similar to Causal DoWhy package's placebo treatment refuter, random cause refuter or sensitivity analysis? I guess k-fold cross validation is similar to data subsampler refuter. What are your thoughts on this? Let me know if you are aware of the industry best practices on this topic.

#machinelearning #causalinference #MMM #datascience #analytics

Related Questions

What are some of Arun Subramanian's most notable achievements at Amazon?
How did Arun Subramanian's role at Nielsen Marketing ROI prepare him for his position at Amazon?
What specific projects has Arun Subramanian led at Amazon?
What are Arun Subramanian's educational background and qualifications?
How has Arun Subramanian's career evolved over the past 12 years?
Arun Subramanian
Arun Subramanian, photo 1
Arun Subramanian, photo 2
Add to my network

Location

Leander, Texas, United States