Free Practice Python Institute PCED-30-01 Exam Questions 2025

Which of the following NumPy methods would you use to apply a function element-wise on a 1-D array, while maintaining the shape of the original array?

Which of the following techniques should be avoided to ensure that your Python data scripting code is easily understandable and follows best practices?

You have a dataset of a retail company's sales transactions, which includes details like customer ID, transaction amount, transaction date, and store ID. You're tasked with summarizing monthly revenue for each store. What would be the most appropriate data aggregation technique?

You are trying to improve a linear regression model by adding polynomial features. After adding the polynomial features, you observe that the model performs much better on the training set but worse on the validation set. What is likely happening?

You're using a Decision Tree classifier to predict whether a transaction is fraudulent. After training, you find that the classifier has a high accuracy on the training set but performs poorly on the test set. Which of the following techniques is most suitable to improve the model's performance?