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Bloom Energy Interview Questions

Bloom Energy Interview Guides

Machine Learning

Encoding Categorical Features

Food Delivery Times

Decision Tree Evaluation

How to model merchant acquisition in a new market?

Merchant Acquisition

Xgboost vs Random Forest

Product Sense & Metrics

Group Success

Instagram TV Success

Amateur Performance

Docs Metrics

WhatsApp Metrics

Write a query to select the top 3 departments with at least ten employees and rank them according to the percentage of their employees making over 100K in salary.

Employee Salaries

Select the 2nd highest salary in the engineering department

2nd Highest Salary

Size of Joins

Analytics

Describing a data project and its challenges

Hurdles In Data Projects

Strategically resolving misaligned expectations with stakeholders for a successful project outcome

Stakeholder Communication

Making data-driven insights actionable for those without technical expertise

Simple Explanations

Brainteasers

How would you answer when an Interviewer asks why you applied to their company?

Why Do You Want to Work With Us

What do you tell an interviewer when they ask you what your strengths and weaknesses are?

Your Strengths and Weaknesses

When an interviewer asks a question along the lines of:

<ul>
<li>What would your current manager say about you? What constructive criticisms might he give?</li>
<li>What are your three biggest strengths and weaknesses you have identified in yourself?</li>
</ul>

How would you respond?

When asked about your strengths in an interview, what is an effective way to respond?

When asked about your strengths in an interview, what is an effective way to respond?

Your Strengths and Weaknesses I

Which of the following is an acceptable strategy when discussing weaknesses in an interview?

Which of the following is an acceptable strategy when discussing weaknesses in an interview?

Your Strengths and Weaknesses II

When an interviewer asks you a question along the lines of:

<ul>
<li>Why did you apply to our company?</li>
<li>What are you looking for in your next job?</li>
<li>What makes you a good fit for our company?</li>
</ul>

How should you respond?

When asked 'What are you looking for in your next job?' in an interview, how can you tie the company's employee benefits into your response?

When asked 'What are you looking for in your next job?' in an interview, how can you tie the company's employee benefits into your response?

Why Do You Want to Work With Us I

How can company values be used effectively in an interview when asked 'What makes you a good fit for our company?'

How can company values be used effectively in an interview when asked 'What makes you a good fit for our company?'

Why Do You Want to Work With Us II

When responding to the question 'Why did you apply to our company?' during an interview, what aspect should you highlight?

When responding to the question 'Why did you apply to our company?' during an interview, what aspect should you highlight?

Why Do You Want to Work With Us III

Describe a data project you worked on. What were some of the challenges you faced?

How would you handle the data preparation for building a machine learning model using imbalanced data?

Addressing imbalanced data in machine learning through carefully prepared techniques.

Data Preparation for Imbalanced Data

Talk about a time when you had trouble communicating with stakeholders. How were you able to overcome it?

Write a SQL query to select the 2nd highest salary in the engineering department.

Note: If more than one person shares the highest salary, the query should select the next highest salary.

Example:

Input:

<code>employees</code> table

<table>
<thead>
<tr>
<th>Column</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>first_name</code></td>
<td>VARCHAR</td>
</tr>

<tr>
<td><code>last_name</code></td>
<td>VARCHAR</td>
</tr>

<tr>
<td><code>salary</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>department_id</code></td>
<td>INTEGER</td>
</tr>
</tbody>
</table>
<code>departments</code> table

<table>
<thead>
<tr>
<th>Column</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>name</code></td>
<td>VARCHAR</td>
</tr>
</tbody>
</table>
Output:

<table>
<thead>
<tr>
<th>Column</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>salary</code></td>
<td>INTEGER</td>
</tr>
</tbody>
</table>

Explain the difference between the XGBoost and random forest algorithms and give an example where you would use one over the other.

Why might a data scientist choose to use XGBoost instead of Random Forest for a particular machine learning task?

Why might a data scientist choose to use XGBoost instead of Random Forest for a particular machine learning task?

XGBoost vs Random Forest: Choice

Create a class named <code>LRUCache</code> that implements the behavior expected of a Least Recently Used (LRU) Cache.

The <code>LRUCache</code> class implements the following methods:

<ul>
<li><code>__init__(self, capacity)</code> - initializes the object and takes in a capacity parameter specifying the maximum capacity of the cache.</li>
<li><code>get_if_exists(self, key) -&gt; Any|None</code> - gets a value based on a key. If the key exists, returns the associated value. If the key has expired or did not exist in the first place, returns <code>None</code>.</li>
<li><code>put(self, key, value)</code> - places a value inside the cache. In the case wherein the cache is full, invalidates the least recently used element. When two keys collide, the older value should be invalidated in place of the new one.</li>
</ul>

Example:

<pre tabindex="0" class="chroma"><code>cache = LRUCache(2)
cache.put(&#34;sample&#34;, 55)
cache.get_if_exists(&#34;sample&#34;) # returns 55
cache.get_if_exists(&#34;key&#34;) # returns None
cache.put(&#34;hello&#34;, 10) 
cache.put(&#34;sample&#34;, 9)
cache.put(&#34;world&#34;, 5)
cache.get_if_exists(&#34;hello&#34;) # returns None
</code></pre>

Notes:

<ul>
<li>It is assured that the value in the <code>put</code> method will never receive a <code>None</code> value. Moreover, it is assured that the capacity will always be &gt; 0.</li>

<li>All operations must be O(1).</li>

<li>Aside from Python’s standard dictionary implementation (<code>{}</code>), you may not use any other built-in data structures.</li>
</ul>

LRU Cache 1

Data Structures & Algorithms

Let’s say you work at Allstate. Allstate is running <code>N</code> online ads right now. The table <code>ads</code> contains all those ads, ranked by popularity via the <code>id</code> column (e.g., the entry with <code>id = 1</code> is the most popular, etc.).

Create a subquery or common table expression named <code>top_ads</code> containing the top 3 ads (by popularity) and return the number of rows that would result from the following operations

<ol>
<li><code>ads INNER JOIN top_ads</code></li>
<li><code>ads LEFT JOIN top_ads</code></li>
<li><code>ads RIGHT JOIN top_ads</code></li>
<li><code>ads CROSS JOIN top_ads</code></li>
</ol>

Note: Please make the <code>join_type</code> column in your output have the values <code>inner_join</code>, <code>left_join</code>, etc. for each of their respective join types

Note: Please return only one query with each number in a different row

Example:

Input:

<table>
<thead>
<tr>
<th>Column</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>name</code></td>
<td>VARCHAR</td>
</tr>
</tbody>
</table>
Output:

<table>
<thead>
<tr>
<th>Column</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>join_type</code></td>
<td>VARCHAR</td>
</tr>

<tr>
<td><code>number_of_rows</code></td>
<td>INTEGER</td>
</tr>
</tbody>
</table>

How would you convey insights and the methods you use to a non-technical audience?

Let’s say you are working on Google Docs. A product manager comes to you and asks how the product is doing. 

What are the top five metrics that you would start tracking to understand the health of Google Docs?

Let’s say you work as a data scientist at a bank.

You are tasked with building a decision tree model to predict if a borrower will pay back a personal loan they are taking out.

<ol>
<li>How would you evaluate whether using a decision tree algorithm is the correct model for the problem?</li>

<li>Let’s say you move forward with the decision tree model. How would you evaluate the performance of the model before deployment and after?</li>
</ol>

Describe a time when you had to define a long-term vision for a project or team and move it from concept to reality.

Interviews for leadership or senior technical roles look for more than just “finishing a project.” Your answer should specifically address:

<ol>
<li>The “Why”: What data or organizational gap necessitated this vision?</li>
<li>The Framework: How did you translate a high-level goal into a roadmap?</li>
<li>The Friction: How did you handle stakeholders or team members who were skeptical of the new direction?</li>
</ol>

Vision Setting and Execution Strategy

Business Case

Given a <code>employees</code> and <code>departments</code> table, select the top 3 departments with at least ten employees and rank them according to the percentage of their employees making over 100K in salary.

Example:

Input:

<code>employees</code> table

<table>
<thead>
<tr>
<th>Columns</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>first_name</code></td>
<td>VARCHAR</td>
</tr>

<tr>
<td><code>last_name</code></td>
<td>VARCHAR</td>
</tr>

<tr>
<td><code>salary</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>department_id</code></td>
<td>INTEGER</td>
</tr>
</tbody>
</table>
<code>departments</code> table

<table>
<thead>
<tr>
<th>Columns</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>name</code></td>
<td>VARCHAR</td>
</tr>
</tbody>
</table>
Output:

<table>
<thead>
<tr>
<th>Column</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>percentage_over_100k</code></td>
<td>FLOAT</td>
</tr>

<tr>
<td><code>department_name</code></td>
<td>VARCHAR</td>
</tr>

<tr>
<td><code>number_of_employees</code></td>
<td>INTEGER</td>
</tr>
</tbody>
</table>

How would you measure the success of Facebook Groups?

Considering the purpose of Facebook Groups as a platform for connecting users through shared interests or real-life relationships, which metrics would be appropriate to measure the success of these groups?

Considering the purpose of Facebook Groups as a platform for connecting users through shared interests or real-life relationships, which metrics would be appropriate to measure the success of these groups?

Let’s say you have analytics data stored in a data lake. An analyst tells you they need hourly, daily, and weekly active user data for a dashboard that refreshes every hour.

How would you build this data pipeline?

Design a data pipeline for hourly user analytics.

Data Pipelines and Aggregation

Data Pipelines

What do you think are the most important metrics for WhatsApp?

What is the optimal strategy for reducing customer churn rate in a messaging platform like WhatsApp?

What is the optimal strategy for reducing customer churn rate in a messaging platform like WhatsApp?

Let’s say you’re a Product Data Scientist at Instagram. How would you measure the success of the Instagram TV product?

What is the primary goal of Instagram TV as a product feature?

What is the primary goal of Instagram TV as a product feature?

Describe an analytics experiment that you designed. How were you able to measure success?

The role of A/B testing in measuring the success rate of an analytics experiment

Success Measurement

A/B Testing

Let’s say you have a categorical variable with thousands of distinct values, how would you encode it?

Which method can be used to extract communities from large networks, that does not require a pre-determined number of clusters like K-means?

Which method can be used to extract communities from large networks, that does not require a pre-determined number of clusters like K-means?

Let’s say that you’re a data scientist at DoorDash.

How would you build a model to predict which merchants the company should go after for acquisition when entering a new market?

Let’s say that you’re in charge of getting payment data into your internal data warehouse.

How would you build an ETL pipeline to get Stripe payment data into the database so analysts can build revenue dashboards and run analytics?

Let's say that you're in charge of getting payment data into your internal data warehouse. 

Payment Data Pipeline

Let’s say you work as a data scientist at DoorDash. 

You are tasked to build a machine learning system that minimizes missing or wrong orders placed on the app.

How would you go about designing this system?

Minimize Wrong Orders

You work as a machine learning engineer for a health insurance company. Design a machine learning model, which given a set of health features, classifies if the individual will undergo major health issues or not.

Creating a machine learning model for evaluating a patient's health

Risk Assessment Model

What are some effective ways to make data more accessible to non-technical people?

Demystifying data for non-technical users through visualization and clear communication

Accessible Data

Data Viz & Interpretation

To improve customer experience on Uber Eats, what key parameters would you focus on improving?

Delivering an exceptional customer experience by focusing on key customer-centric parameters

Uber Eats Customer Experience

Let’s say we’re working on a new feature for LinkedIn chat. We want to implement a green dot to show an “active user” but given engineering constraints, we can’t AB test it before release.

How would you analyze the effectiveness of this new feature?

Green Dot

Let’s say you’re a data scientist working on pricing different products on our ecommerce site. The online price is dependent on the availability of the product, the demand, and the logistics cost of providing it to the end consumer. 

You discover our algorithm is vastly under-pricing a certain consumer product. What are the steps you take in diagnosing the problem?

Underpricing Algorithm

How would you measure success for Facebook Stories?

Measure Facebook Stories success by tracking reach, engagement, and actions aligned with specific business goals

Facebook Story Success

Let’s say that you’re a data scientist working for Facebook.

You’ve been asked to generate a machine learning model that can map the legal first name of a person to likely nicknames they might have.

How do you go about designing this model?

Mapping Nicknames

Challenge

At Bloom Energy, our mission is to make clean, reliable energy affordable for everyone in the world. We created the first large-scale, commercially viable solid oxide fuel-cell based power generation platform that empowers businesses, essential services, critical infrastructure and communities to responsibly take charge of their energy.Our technology, invented in the United States, is one of the most advanced electricity and hydrogen producing technologies on the market today. We currently are recruiting individuals that meet the requirements to be a part of our team for our SEC Reporting department, which develops or assists in providing the required filings (10K, 10Q, 8K, annual report, proxy filing, statutory and other SEC filings) to the SEC. This high visibility position will be responsible for the following:<ul><li>Assist the SEC Reporting Manager in interfacing with others, including senior management, external auditors and consultants regarding accounting and financial reporting issues to ensure compliance with U.S. GAAP and SEC regulations</li><li>Assist in developing monthly and quarterly financial reporting calendars and project plans and communicating key dates.</li><li>Assist in the Company’s external financial reporting process, including quarterly and annual reporting (Form 10-Q and Form 10-K), other SEC filings, and develop standard report templates for disclosure information to be reported by accounting and finance teams.</li><li>Work closely with all members of the Corporate Controller’s Team to prepare and deliver external financial reporting – including quarterly earnings release materials and required SEC filings (10K, 10Q, 8K, annual report, statutory and other miscellaneous SEC filings)</li><li>Assist in the coordination of external reporting activities to prepare and deliver external financial reporting and related earnings release materials associated with quarterly and annual filings, while working closely with Leadership (primarily Controller teams and Legal Department)</li><li>Serves as the primary resource in managing the flow of financial data into BE’s SEC filing tool, Workiva</li><li>Participate in the review of new and unusual transactions to ensure that they are recorded in compliance with US GAAP</li><li>Utilize accounting research tools to ensure our public filings are following US GAAP and SEC regulations</li><li>Assist in preparing Audit Committee presentations and the supporting quarterly financial supplemental package.</li><li>Reconcile net income to EBITDA and compute comparable EBITDA</li><li>Assist in preparation of key financial reports, including consolidated Balance Sheets, Statement of Operations, Statement of Comprehensive Income or Loss, Cap table, Cash Flow Statement, Statement of Equity, and Notes to Consolidated Financial Statements.</li><li>Become leader of the Tic and Tie process that ensures accurate information is transferred from the accounting ledgers to the SEC Reporting tool Workiva, including the rolling forward of previously reported information.</li><li>Manage the SEC submission checklists and provide archiving of supporting files.</li><li>Assist in the research of accounting issues, new accounting pronouncements and their impact on the Company.</li><li>Assist auditors in review of financial statements and resolution of issues prior to filing.</li><li>Maintain the XBRL taxonomy and assist in the XBRL filings.</li><li>Assist in ad-hoc requests relating to SEC Reporting.</li></ul>Qualification for this position includes:<ul><li>CA/CA inter, CPA Degree, with 3-6 experience in accounting or finance at a large corporation of public accounting firm.</li><li>Experience with Workiva WDesk is a plus.</li><li>Flexible and team-oriented</li><li>Ability to maintain strict confidentiality of corporate level accounting information.</li><li>Strong knowledge of GAAP and SEC Reporting Requirements.</li></ul>

<h5>Staff Data Scientist </h5>At Bloom Energy, our vision for a world powered by clean, reliable, and affordable energy is more than just a dreamwe're making it reality. For over two decades, we've been at the forefront of the global energy transition, pioneering solutions that empower critical industries to thrive in a rapidly digitizing, energy-intensive world. From revolutionizing power for AI-driven data centers to ensuring resilience for hospitals, electric grids, manufacturing facilities, and utilities, our solid oxide fuel cell (SOFC) and solid oxide electrolyzer (SOEC) technologies are redefining what's possible by delivering energy abundance for all. With more than 30,000 fuel cell modules deployed worldwide, we are the trusted partner for Fortune 100 companies and innovators alike. Our cutting-edge solutions enable unparalleled "time-to-power" capabilities, reliability, and sustainability, ensuring our customers remain ahead in a world where soaring energy demand and intensifying energy scarcity are rapidly becoming the new norm. At Bloom, we thrive on collaboration, bold thinking, and relentless innovation. We believe that, together, we can create a brighter, more sustainable future while tackling the most pressing challenges of the 21st century. We are looking for a Staff Data Scientist to join our team in one of today's most exciting technologies. This role will report to the Factory Engineering Director and is based in Fremont, CA. This is a fully on-site, in office role. Role and Responsibilities: <ul> <li>Develop predictive and prescriptive models for yield improvement, scrap reduction, cycle-time optimization, and equipment reliability. </li><li>Build anomaly detection models and statistical process control (SPC)driven insights to monitor production health. </li><li>Apply machine learning techniques (classification, regression, clustering, time-series forecasting) to high-volume sensor and production data. </li><li>Analyze complex multi-step manufacturing workflows to identify bottlenecks and root causes of variation. </li><li>Partner with process engineers to translate data insights into measurable operational improvements. </li><li>Identify opportunities for automation and advanced analytics as part of Lean / Six Sigma / Digital Transformation initiatives. </li></ul> Skills and Experience: <ul> <li>Bachelor's degree in data science, statistics, computer science, engineering or a related technical field. </li><li>7+ years of experience in data science or advanced analytic roles. </li><li>Strong proficiency in: </li><ul> <li>Python or R </li><li>SQL </li><li>Statistical analysis and experimental design </li></ul> <li>Experience in high-volume manufacturing environments (e.g., electronics, automotive, semiconductor, medical devices, chemicals). </li></ul> Physical Requirements (optional): <ul> <li>Prolonged periods of standing and performing repetitive tasks. </li><li>Must be able to lift up to 25 lbs. at a time. </li><li>Must have manual dexterity in order to assemble products as directed. </li><li>Must have excellent hand-eye coordination </li><li>Must wear Personal Protective Equipment (PPE) </li></ul> Bloom Energy is an equal opportunity employer and makes employment decisions on the basis of merit. We are committed to compliance with all applicable laws providing equal employment opportunities. All qualified applicants will receive consideration for employment without regard to race, sex, color, religion, national origin, protected veteran status, or on the basis of disability. Bloom Energy makes reasonable accommodations, consistent with applicable laws, for the known physical or mental limitations of an otherwise qualified applicant or employee with a disability, who can perform the essential job functions, unless undue hardship would result. At Bloom Energy, we are committed to supporting the well-being of our employees and their families. Our comprehensive benefits package for eligible employees includes competitive Medical, Dental, and Vision plans with a large employer contribution, a 401(k) Retirement Plan with company match, generous Mental Health Support services, Legal services, virtual Physical Therapy access, and Fertility & Family Forming benefits. Bloom Energy is committed to fair and equitable compensation practices. The total compensation for this position includes standard company benefits and is based on various factors including, but not limited to, relevant skills and experience. $112,300.00 - $161,700.00

Calculate Moving Average	SQL	Easy
Predict Customer Churn	Machine Learning	Medium
A/B Test Significance	Statistics	Medium
Optimize Query Performance	SQL	Hard
Feature Importance Analysis	Machine Learning	Medium
Clean Missing Data	Python	Easy
Neural Network Architecture	Deep Learning	Hard
Calculate Cohort Retention	SQL	Medium
Bayesian Probability	Statistics	Easy
Recommend Similar Products	Machine Learning	Hard

Bloom Energy Interview Questions

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Bloom Energy Interview Questions

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