Data Science Associate Interview Questions and Answers for Freshers

Box-plot is a visual representation of the distribution of a dataset, showing the median, quartiles, and outliers.

• Box-plot displays the median (middle line), quartiles (box), and outliers (dots or lines).

• The length of the box represents the interquartile range (IQR).

• Whiskers extend to the smallest and largest non-outlier data points within 1.5 times the IQR from the quartiles.

• Outliers are plotted individually as dots or lines beyond the whiskers.

• Box-plots are useful for compa...read more

Outliers can be handled by identifying, analyzing, and either removing or transforming them in the data.

• Identify outliers using statistical methods like Z-score or IQR.

• Analyze the outliers to understand if they are errors or valid data points.

• Remove outliers if they are errors or transform them using techniques like winsorization or log transformation.

• Consider using robust statistical methods that are less sensitive to outliers.

• Visualize the data to identify outliers visually...read more

Standardisation and normalisation are techniques used to scale and transform data in order to improve model performance.

• Standardisation (Z-score normalisation) scales the data to have a mean of 0 and a standard deviation of 1.

• Normalisation (Min-Max scaling) scales the data to a specific range, typically between 0 and 1.

• Standardisation is less affected by outliers compared to normalisation.

• Standardisation is preferred when the data follows a normal distribution, while normalis...read more