PCED study guide
PCED · Work through your exam, one topic at a time.
PCED – Certified Entry-Level Data Analyst with Python is an entry-level Python Institute certification (exam code PCED-30-02, active since July 15, 2025) that confirms foundational knowledge of data analytics and Python programming. It is aimed at complete beginners, aspiring data analysts, students and career changers, professionals in non-technical roles, and educators who want a structured first credential in data work. The PCED study guide has 6 sections and about 2,252 words.
01Data Collection Fundamentals
Data collection fundamentals covers where data comes from and how it is gathered: source types, measurement scales, sampling methods and the biases they introduce, and the quality checks applied before any cleaning or analysis begins. Exam items ask you to classify a variable, name the sampling technique used, or explain why a huge sample can still mislead.
363 words, about 2 min02Organizing and Cleaning Data
This domain tests turning a messy extract into a tidy, typed, documented dataset: reshaping to one row per observation, handling missing values and duplicates, standardizing text and types, and catching outliers and out-of-range values without destroying information. Tidy structure: one row per observation, one column per variable, one table per observational unit.
406 words, about 2 min03Transformation and Analysis with Built-ins and Essential Libraries
Practical analysis with the standard library and NumPy: reading CSV, summarizing numbers, handling dates, counting and grouping, and doing vectorized arithmetic on arrays. Expect code-reading items ("what does this print?") and items asking which tool fits a task.
359 words, about 2 min04Drawing Basic Insights and Communicating Findings
Items ask you to convert analysis into a clear, defensible summary: writing an insight statement, choosing the right chart for the question, and reporting change and uncertainty honestly. Structure each insight as finding, evidence, implication: "Checkout abandonment rose from 62% to 71% (+9 percentage points) between Q1 and Q2, concentrated in mobile users." Always state n, the time window and the unit: "median order value, USD", not "average value".
381 words, about 2 min05Data Ethics, Visualization and Storytelling Concepts
Ethics items cover privacy, consent and honest reporting; visualization items cover encoding accuracy and accessibility; storytelling items cover audience, message and structure. Collect only what the question needs (data minimisation) and state the purpose up front.
366 words, about 2 min06Python Built-ins for Data Work
Pure-Python mechanics behind every data script: variables and types, the core containers, file handling, control flow and functions. Questions are usually short code traces - predict the output or spot the bug.
377 words, about 2 min