Estimating Google Maps Street View Storage: A Guide for Product Manager Interviews
Introduction
This blog post will guide you through a critical component of the product manager interview process at leading tech companies like FAANG: estimating substantial data figures. We’ll focus on a prevalent interview question candidates might encounter: **”How much storage does Google Maps Street View take?”** Understanding how to navigate this question with a structured response is essential for showcasing your analytical prowess and problem-solving capabilities.
Detailed Guide on Framework Application
In product management interviews, a suitable framework for data estimation is the **Fermi Estimation**, which breaks down complex problems into manageable parts to estimate values that are not readily available.
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a. Fermi Estimation:
Named after physicist Enrico Fermi, this approach involves making educated guesses based on logical steps.
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b. Applying the Framework:
1. **Identify the variables:** Start by outlining the variables that contribute to the total storage needed, such as image size, number of locations, and frequency of updates.
2. **Estimate each variable:** Use general knowledge, comparisons, and assumptions to estimate each variable. For example, the average size of a Street View image might be 10MB, considering high-resolution panoramas.
3. **Aggregate estimates:** Multiply the estimates of the variables to get the total storage estimate. If we estimate a billion locations with four updates a year, that leads to four billion images, equaling an estimate of 40 petabytes of data annually.
4. **Example:** Illustrating this with a hypothetical case, if Google Maps Street View captures 10 million miles of roads globally, with an average of 5,280 feet per mile and one photo every 10 feet, you would estimate around 5,280 images per mile. Multiply this by 10 million miles to get the total number of images.
5. **Facts Check:** While you might not know precise figures, it’s crucial to make intelligent guesses that sound reasonable, such as assuming the intervals at which photos are taken or the average resolution used by current digital cameras.
6. **The candidate should approach the problem with clarity, acknowledging data limitations, and offer a logical rationale for their assumptions.**
7. **Communication Tips:** Speak clearly, lay out your estimation process step by step, and summarize your final estimate succinctly. It’s important to show your thinking process and how you handle incomplete information.
Conclusion
Estimation questions like determining the storage for Google Maps Street View test your analytical thinking and problem-solving skills—a core aspect of product management. By using the Fermi Estimation framework, you can break down the problem and provide a structured, logical answer. Remember, practice is essential. Routinely apply these frameworks to different scenarios to enhance your technique and confidence ahead of your FAANG interviews.