83 interview questions for Chief Data officer (2026)

Medium

21 votes1636 runs0 comment

How to handle missing data in a given training data set ?

Data Scientist

machine learning

missing data

Martinat Apr 4, 2022

Easy

18 votes942 runs0 comment

What is the missing word in the following sentence: Overfitting is the production of a model that corresponds too closely to the training data set and may therefore fail to fit other data sets and so fail to perform any reliable forecast.

Data Scientist

overfitting

Martinat Mar 14, 2022

Easy

16 votes917 runs0 comment

What is the relation between Artificial intelligence (AI), machine learning and deep learning?

Data Scientist

machine learning

deep learning

Martinat Sep 19, 2022

Medium

12 votes1589 runs0 comment

The validation set is used to provide frequent and unbiased evaluations of the model’s fit on the training set while tuning its hyperparameters/parameters: in other words,the model is found and then tested on the validation set before to be improved once again.

Data Scientist

hyperparameters

model

Martinat Mar 15, 2022

Medium

12 votes1481 runs0 comment

How to handle missing data in a given training data set ?

Data Scientist

machine learning

missing data

Martinat Apr 4, 2022

Easy

12 votes1127 runs0 comment

What is the value of the decision threshold used with logistic regression in Scikit-learn?

Data Scientist

scikit-learn

threshold

logistic regression

Anonymous authorat Apr 6, 2022

Hard

8 votes1455 runs

2 comments

What are the differences/similarities between a loss function, an error function, and a cost function?

Data Scientist

loss function

error function

cost function

Martinat Mar 15, 2022

Easy

8 votes922 runs0 comment

Given a neural network with 4 inputs, how many connections could exist between the input layer and the first hidden layer?

Data Scientist

neural network

connections

Martinat Apr 4, 2022

Easy

7 votes1501 runs0 comment

What is the missing word in the following sentence: Overfitting is the production of a model that corresponds too closely to the training data set and may therefore fail to fit other data sets and so fail to perform any reliable forecast.

Data Scientist

machine learning

overfitting

Martinat Mar 15, 2022

Easy

7 votes1361 runs0 comment

Clustering is an unsupervised machine learning process which aims at automatically discovering natural grouping in the input data. When using this method, the developer is able to choose the number of groups he wants to create.

Data Scientist

machine learning

unsupervised learning

Martinat Mar 15, 2022

Medium

6 votes1384 runs0 comment

How to assess a clustering model performances?

Data Scientist

metrics

clustering

Martinat Mar 15, 2022

Easy

6 votes851 runs0 comment

Which of the following processes are machine learning ones but not particularly related to deep learning?

Data Scientist

machine learning

random forest

Martinat Mar 14, 2022

Easy

5 votes1517 runs0 comment

Given a data set, which elements will help you to choose what model / machine learning method to use to create an efficient model?

Data Scientist

data

model

Martinat Mar 15, 2022

Hard

5 votes1425 runs0 comment

Which of the following statements are true when considering stacking?

Data Scientist

ensemble

machine learning

Martinat Mar 15, 2022

Easy

5 votes1416 runs0 comment

In order to get good results when implementing deep learning, one needs to prepare his data before using it. What action should be done during this preparation?

Data Scientist

data

preprocessing

Martinat Mar 15, 2022

Easy

5 votes1356 runs0 comment

How to define supervised learning? In supervised learning, the machine trains the model using a labeled training data set.

Data Scientist

supervised learning

machine learning

Martinat Mar 15, 2022

Hard

5 votes1077 runs0 comment

How to get the size of an array in scikit-learn

Data Scientist

scikit-learn

numpy

array

Anonymous authorat Apr 6, 2022

Medium

4 votes1433 runs1 comment

Which of the following actions can be used during the date pre-processing when performing regression or classification?

Data Scientist

data

preprocessing

Martinat Dec 13, 2023

Medium

4 votes1431 runs0 comment

Which of the following statements is true when considering machine learning?

Data Scientist

machine learning

artificial intelligence

computer science

Martinat Mar 15, 2022

Easy

4 votes1023 runs1 comment

Reshape a 2x4 array into a 2x2x2 array in scikit-learn

Data Scientist

scikit-learn

numpy

reshape

Anonymous authorat Jan 30, 2023

83 interview questionsfor Chief Data officer (2026)

Test your technical skills before an interview of Chief Data officer with 83 corrected questions. Beginner, Intermediate or Expert level.

How to handle missing data in a given training data set ?

What is the missing word in the following sentence: Overfitting is the production of a model that corresponds too closely to the training data set and may therefore fail to fit other data sets and so fail to perform any reliable forecast.

What is the relation between Artificial intelligence (AI), machine learning and deep learning?

The validation set is used to provide frequent and unbiased evaluations of the model’s fit on the training set while tuning its hyperparameters/parameters: in other words,the model is found and then tested on the validation set before to be improved once again.

How to handle missing data in a given training data set ?

What is the value of the decision threshold used with logistic regression in Scikit-learn?

What are the differences/similarities between a loss function, an error function, and a cost function?

Given a neural network with 4 inputs, how many connections could exist between the input layer and the first hidden layer?

What is the missing word in the following sentence: Overfitting is the production of a model that corresponds too closely to the training data set and may therefore fail to fit other data sets and so fail to perform any reliable forecast.

Clustering is an unsupervised machine learning process which aims at automatically discovering natural grouping in the input data. When using this method, the developer is able to choose the number of groups he wants to create.

How to assess a clustering model performances?

Which of the following processes are machine learning ones but not particularly related to deep learning?

Given a data set, which elements will help you to choose what model / machine learning method to use to create an efficient model?

Which of the following statements are true when considering stacking?

In order to get good results when implementing deep learning, one needs to prepare his data before using it. What action should be done during this preparation?

How to define supervised learning? In supervised learning, the machine trains the model using a labeled training data set.

How to get the size of an array in scikit-learn

Which of the following actions can be used during the date pre-processing when performing regression or classification?

Which of the following statements is true when considering machine learning?

Reshape a 2x4 array into a 2x2x2 array in scikit-learn