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StatisticsML Knowledge
a year ago
In what way does PCA work and what are some of its cons?
Data ScientistMachine Learning Engineer

BetterUp

Shutterstock

Improbable

PCA, or principal component analysis, is a process to determine what are the most important features. I like to think about it in terms of eigenvalues. If you have a diagonal matrix, then the eigenvalues are the diagonal terms, and the eigenvectors are the basis vectors. In PCA, the principal components and their effects aren't as visible, but it is a process to determine them. If I recall correctly, PCA will return the absolute value of the eigenvalues, rather than the eigenvalue itself. 



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a year ago
SQL
a year ago
In terms of SQL, what are the key differences between a left join, a right join, and a union?
Data Scientist

BetterUp

Benchling

Illumina

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a year ago
Behavioral
a year ago
Describe the typical workflow of a Data Science project from start to finish.
Data Scientist

BetterUp

Cisco Logo

Cisco

Arm Logo

Arm

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a year ago
Statistics
2 years ago
Can you discuss some of the consequences of ignoring multicollinearity in regression analysis?
Data Scientist

BetterUp

Stitch Fix Logo

Stitch Fix

NetEase Logo

NetEase

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2 years ago
ML Knowledge
2 years ago
Is there anything you can tell me about attention mechanisms in neural networks?
Data Scientist

BetterUp

Convoy Logo

Convoy

Bloomberg Logo

Bloomberg

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2 years ago
Behavioral
2 years ago
Tell us about a time when you made a big mistake at work.
Data ScientistData Engineering ManagerUX ResearcherEngineering Manager

BetterUp

Box Logo

Box

Amdocs Logo

Amdocs

+1

I was managing organization wide restructuring program where goal was to map all resources with their delivery accounts to keep a track of account’s PnL and manage capability as cost centre. We also intended to design KRA and KPIs for each individual level to make our Performance Assessment data driven and transparent. This was a big change at employee level at professional and emotional level too. It meant changes in their reporting structures, extra reporting and performance management by all managers, clear KPIs alignment and selection.

Planning Level: We identified all the major business account heads, capability and other function head and organized a communication platform to make them aware and comfortable with the changes. We undertook their inputs on pros and cons and some caution to be exercised

Execution Level: We started executing these changes with L0 level employees and moved up to leadership team. Along the way we encountered some risks and outlier conditions to be managed.

Communication Strategy: We worked with all business and functional heads on our communication strategy to reach out to all the employees. Head multiple events and workshops to discuss the changes.

Data Platform changes: Evaluated all the data platform changes required and planned a phased out approach to bring those changes in the system as well.

However, when we were about to reach closure of this program, I realized that I have made a big mistake of readiness of our existing platforms to support all the changes required and existing data integrity. It really took a toll on everyone involved to clear up data accuracy before the changes could be introduced.

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2 years ago
ML Knowledge
2 years ago
Can you explain how you tackle data skew in model performance evaluations and the metrics that are useful in such situations?
Data ScientistMachine Learning Engineer

BetterUp

SeatGeek Logo

SeatGeek

Chime Logo

Chime

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2 years ago
StatisticsCoding
2 years ago
How would you code a shuffle() function that randomizes an array uniformly using roll()?
Data Scientist

BetterUp

Udacity Logo

Udacity

Klarna Logo

Klarna

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2 years ago
Behavioral
2 years ago
Tell me about a time where you were unpopular thanks to a decision you imposed on your team
Data ScientistSoftware EngineerTechnical Program ManagerBackend Engineer

BetterUp

Deliveroo Logo

Deliveroo

Pendo Logo

Pendo

+6

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2 years ago
Behavioral
2 years ago
What did you do when you missed a deadline?
Data ScientistTechnical Program ManagerSoftware EngineerML Engineering Manager

BetterUp

Decathlon Logo

Decathlon

NVIDIA Logo

NVIDIA

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2 years ago

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*All interview questions are submitted by recent BetterUp Data Scientist candidates, labelled and categorized by Prepfully, and then published after being verified by Data Scientists at BetterUp.

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