FreeCampus Python

Data Science Overview

Turn questions and datasets into cleaned, analyzed, visualized, and communicated results.

data-science

How to use this chapter hands-on

This chapter is about Data Science. Do not read it like a reference manual. Use it as a sequence of short labs. For each lesson, open the Colab notebook from the button above, run Example 1, write a prediction, and then change one small part of the code.

By the end of the chapter, you should have one small artifact: a notebook, a script, a trace table, or a project note. The artifact should show one working example, one controlled variation, and one error or surprising result that you investigated calmly.

If time is short, study one lesson deeply instead of skimming all of them. A deeply understood example is one you can run again, explain in plain language, modify safely, and debug when it breaks.

Why this chapter matters

Turn questions and datasets into cleaned, analyzed, visualized, and communicated results.

Lessons are now grouped by coherent learner topics. A page may contain multiple short quizzes when the page has multiple sections, so students can check one idea before moving to the next.

Guiding questions

Which lessons belong in this chapter?
What should I review before moving on?
How do the lesson sections build one practical skill?

Lesson path

Workflow and Loading Data — Move from question to dataset and load tabular data with pandas.
Inspecting, Selecting, and Cleaning — Understand DataFrames, choose relevant data, and handle missing values.
Grouping and Statistics — Summarize categories and describe distributions.
Visualization with seaborn — Create statistical plots with seaborn.
Communicating Results — Explain findings with evidence, uncertainty, and limitations.

Chapter checkpoint

Use this short checkpoint before starting the chapter.

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  }

  script.dataset.fcpythonRendered = "true";
  const quiz = JSON.parse(script.textContent);
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  const title = document.createElement("h3");
  title.textContent = quiz.title;
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  instructions.textContent = quiz.instructions;
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  counter.setAttribute("aria-live", "polite");
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  const tabs = document.createElement("div");
  tabs.className = "fcpython-quiz-steps";
  tabs.setAttribute("role", "tablist");
  tabs.setAttribute("aria-label", "Quiz questions");
  progress.appendChild(tabs);
  container.appendChild(progress);

  const questions = document.createElement("div");
  questions.className = "fcpython-quiz-questions";

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    const question = quiz.questions[questionIndex];
    const statuses = {
      answered: "answered",
      correct: "correct",
      incorrect: "incorrect",
      unanswered: "not answered",
    };

    step.classList.remove(
      "is-answered",
      "is-correct",
      "is-incorrect",
      "is-unanswered"
    );
    if (status) {
      step.classList.add(`is-${status}`);
    }

    const statusLabel = status ? `, ${statuses[status]}` : "";
    step.setAttribute(
      "aria-label",
      `Question ${questionIndex + 1}: ${question.prompt}${statusLabel}`
    );
  }

  function showQuestion(questionIndex, focusPanel = false) {
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      step.classList.toggle("is-current", isCurrent);
      step.setAttribute("aria-selected", String(isCurrent));
      step.tabIndex = isCurrent ? 0 : -1;
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    counter.textContent = `Question ${currentQuestion + 1} of ${quiz.questions.length}`;

    const selected = questionPanels[currentQuestion].querySelector(
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    const isLastQuestion = currentQuestion === quiz.questions.length - 1;
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    check.hidden = !isLastQuestion;

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    step.addEventListener("click", () => showQuestion(questionIndex));
    step.addEventListener("keydown", (event) => {
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      if (event.key === "ArrowRight") {
        destination = (questionIndex + 1) % quiz.questions.length;
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        destination =
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      } else if (event.key === "Home") {
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        destination = quiz.questions.length - 1;
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        stepButtons[destination].focus();
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    stepButtons.push(step);
    tabs.appendChild(step);
    setStepStatus(questionIndex, "");

    const panel = document.createElement("div");
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    question.options.forEach((option, optionIndex) => {
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      label.className = "fcpython-quiz-option";

      const input = document.createElement("input");
      input.type = "radio";
      input.name = `${quiz.id}-${question.id}`;
      input.value = String(optionIndex);
      input.addEventListener("change", () => {
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        feedbackNodes[questionIndex].textContent = "";
        feedbackNodes[questionIndex].className = "fcpython-quiz-feedback";
        score.textContent = "";
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      text.textContent = option;

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      fieldset.appendChild(label);
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    const feedback = document.createElement("p");
    feedback.className = "fcpython-quiz-feedback";
    feedback.setAttribute("aria-live", "polite");
    feedbackNodes.push(feedback);
    fieldset.appendChild(feedback);
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    questionPanels.push(panel);
    questions.appendChild(panel);
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  container.appendChild(questions);

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  actions.className = "fcpython-quiz-actions";

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  previous.textContent = "Previous";
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  next.textContent = "Next question";
  next.addEventListener("click", () => {
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  check.type = "button";
  check.textContent = "Check answers";

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  reset.type = "button";
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  reset.textContent = "Reset";

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        feedback.className = "fcpython-quiz-feedback";
        setStepStatus(questionIndex, "unanswered");
        if (firstQuestionToReview === null) {
          firstQuestionToReview = questionIndex;
        }
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      const selectedIndex = Number(selected.value);
      if (selectedIndex === question.answer_index) {
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      feedback.className = "fcpython-quiz-feedback";
    });
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      setStepStatus(questionIndex, "");
    });
    score.textContent = "";
    showQuestion(0, true);
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  actions.appendChild(next);
  actions.appendChild(check);
  actions.appendChild(reset);
  container.appendChild(actions);
  container.appendChild(score);
  showQuestion(0);
  return container;
}