Top Data Scientist Interview Questions

It is obvious to get nervous during your interview. To prepare you for your interview, we have listed possible questions and answers which will help you. Read till the end of the article, and be prepared for your coming interview on data sciences.

What are the applications of data science?

There are several applications of data sciences. Data Sciences helps us to identify and also predict different types of diseases. With the help of data Sciences, a personalized recommendation of Healthcare is available to the people. Optimization of shipping routes and looking into different types of crimes and frauds can be made easy with the help of data Sciences. Data mining, machine learning, and big data are related to data science, which uses several algorithms and methods.

Data Sciences are also helpful in extracting different types of knowledge from unstructured data and structural data. The other data sciences applications also include data generation in governmental policies, marketing, and human resources. The data scientists are responsible for the industries impacted by data and the application areas look into business logistics and analytics. There is no sector or industry which will not be influenced by data Sciences and data scientist. 

Describe some of the steps related to data wrangling and cleaning of data before applying machine learning algorithms.

Different types of steps are related to data wrangling, and cleaning of data. At first come data profiling, where everyone starts from understanding the data profiling and the database. This is the beast, and more specifically, the shape and description of the different numerical variables are related to the data set. After that comes data visualization, which is useful for visualizing box plots and data. It is also useful for understanding the different types of relationships between variables and identifying the potential outlets. After that comes syntax errors, which includes making sure that there is no white space, it also cheques for different types of typos by using unique bar graphs.

After that comes strength standardization or normalization, which looks into the database and depends on the machine’s learning method normalizing the different skills and variables impacting the models’ performance. Other things include her handling null values through which the rows can be deleted, and the values can be predicted. 

How will you deal with unbalanced binary classification?

There are several ways through which unbalanced binary classification can be handled. At first, the matrix has to be reconsidered, and the evaluation of the model has to be done. The accuracy of the particular model might not go with the best metrics, and that is why there are specific considerations of the precision of the metrics that have to be seen. After that, another method to improve the aspects related to binary classification is by increasing the minority classes cost of misclassification. By increasing the penalty, the model might have certain accuracy. Finally, there is also a balance of classes that can be done by undersampling and oversampling.

What is the main difference between a histogram and a box plot?

Histograms and box plots are incredibly different from each other. Histograms can be considered the type of bar charts that show the frequency of numerical variables and their values. It is also used to understand the shape, the different distributions, the potential outlets, and the variations. Box plots can communicate with other distributions of data and spectrums through which the shape of the distribution can range through outlets. Box plots are also responsible and useful through comparing multiple shots, and it takes less space than the histogram. 

Tell me, what is cross-validation?

Cross-validation can be considered the type of technique that is exceptionally crucial for accessing the model and its performance on the independent database. Cross-validation can also be considered the training data and testing data through which the model will be successful.

What is NLP?

NLP stands for the phrase also known as natural language processing. Natural language processing is also considered the branch of artificial intelligence related to the machinery and can understand different types of human languages and read them.

Is dimension reduction necessary? Why?

Dimension reduction is significant because it is the process through which reducing the number of features in the database is done. This process is crucial because the model’s variance and overfitting and the underfitting can be described with the help of dimension reduction. There are certain advantages of dimension reduction as it reduces the storage base and the time required for the whole process. After that, it is also helpful because removing different multi Co linearity is done it improves the interpretation of the model and machine learning parameters. After that, it avoids the different types related to the dimension, and it is also easy to visualize. The low dimensions are ready to visualize, and the data is reduced for it. 

Explain the drawbacks of a linear model.

There are certain types of drawbacks of a linear model. A linear model always tends to hold different types of strong assumptions that might not be extremely true when applied in different processes. At first, it assumes the relationship of the linear theory and the auto co-relational theory, but it is different in application. After that, a linear model is not flexible at all, which is one of the most significant drawbacks. The third drawback of the linear model is that it cannot be used for binary outcomes or discrete outcomes. 

What is a decision tree?

A decision tree is one of the most popular models that have been used in data Sciences. A decision tree is also used in different operational research and machine learning, and strategic planning in various industries. There are several squares in the decision tree, and each square is called a node. There are many nodes in the decision tree, and the last note of the decision tree will make a particular decision or the primary leave of the tree. 

Being a data scientist might not be easy, but we have the proper solution for you. Read these questions and answers and rock your interview.