Find Interview Questions for Do it lean

Right Answer:
To handle missing data in a dataset, you can use the following methods:

1. **Remove Rows/Columns**: Delete rows or columns with missing values if they are not significant.
2. **Imputation**: Fill in missing values using techniques like mean, median, mode, or more advanced methods like KNN or regression.
3. **Flagging**: Create a new column to indicate missing values for analysis.
4. **Predictive Modeling**: Use algorithms to predict and fill in missing values based on other data.
5. **Leave as Is**: In some cases, you may choose to leave missing values if they are meaningful for analysis.

Right Answer:
Outliers are data points that significantly differ from the rest of the dataset. They can skew results and affect statistical analyses. To handle outliers, you can:

1. Identify them using methods like the IQR (Interquartile Range) or Z-scores.
2. Remove them if they are errors or irrelevant.
3. Transform them using techniques like log transformation.
4. Use robust statistical methods that are less affected by outliers.
5. Analyze them separately if they provide valuable insights.

Right Answer:
Correlation is a statistical measure that indicates the extent to which two variables fluctuate together, while causation implies that one variable directly affects or causes a change in another variable.

Right Answer:
Exploratory Data Analysis (EDA) is the process of analyzing and summarizing datasets to understand their main characteristics, often using visual methods. It helps identify patterns, trends, and anomalies in the data before applying formal modeling techniques.

Right Answer:
The different types of data distributions include:

1. Normal Distribution
2. Binomial Distribution
3. Poisson Distribution
4. Uniform Distribution
5. Exponential Distribution
6. Log-Normal Distribution
7. Geometric Distribution
8. Beta Distribution
9. Chi-Squared Distribution
10. Student's t-Distribution

Right Answer:
RESTful principles include:

1. **Statelessness**: Each API call must contain all the information needed to understand and process the request, with no stored context on the server.
2. **Client-Server Architecture**: The client and server are separate, allowing for independent development and scalability.
3. **Uniform Interface**: A consistent way to interact with resources, typically using standard HTTP methods (GET, POST, PUT, DELETE).
4. **Resource-Based**: APIs should expose resources (data entities) through URIs, and clients interact with these resources.
5. **Representation**: Resources can be represented in various formats (like JSON or XML), and clients can request the format they prefer.
6. **Cacheability**: Responses should indicate whether they can be cached to improve performance and reduce server load.

These principles guide the design of APIs to be scalable, efficient, and easy to use.

Right Answer:
OAuth is an open standard for access delegation commonly used for token-based authentication and authorization. It allows third-party applications to access a user's resources without sharing their credentials.

In API authentication, OAuth works by having the user authorize the application to access their data. The process involves:

1. The user is redirected to an authorization server to log in and grant permission.
2. The authorization server issues an access token to the application.
3. The application uses this access token to make API requests on behalf of the user.
4. The API validates the token and grants access to the requested resources.

Right Answer:
HTTP methods are standardized request types used in APIs to perform actions on resources. The main methods are:

1. **GET**: Retrieve data from a server.
2. **POST**: Send data to a server to create a new resource.
3. **PUT**: Update an existing resource on the server.
4. **DELETE**: Remove a resource from the server.
5. **PATCH**: Apply partial modifications to a resource.

These methods define the action to be performed on the specified resource in the API.

Right Answer:
JSON (JavaScript Object Notation) is a lightweight data interchange format that is easy for humans to read and write, and easy for machines to parse and generate. In APIs, JSON is commonly used to format data exchanged between a client and a server, allowing for structured data representation in requests and responses.

Right Answer:
REST (Representational State Transfer) is an architectural style that uses standard HTTP methods and is typically more lightweight and easier to use, while SOAP (Simple Object Access Protocol) is a protocol that relies on XML for message format and has strict standards for security and transactions. REST is generally more flexible and faster, while SOAP is more suited for enterprise-level services requiring high security and reliability.