Year 7 Edexcel Statistics: Case Study Practical Exercises | 七年级爱德思统计：案例分析实战演练

📚 Year 7 Edexcel Statistics: Case Study Practical Exercises | 七年级爱德思统计：案例分析实战演练

In Year 7 Edexcel Statistics, students develop essential data handling skills by working through real-world scenarios. This case study takes you step by step through a practical investigation, from designing a survey to interpreting results. You will practise collecting data, creating tables and charts, calculating averages and the range, and using these to draw meaningful conclusions. Let’s dive into a complete statistical project based on a school canteen survey.

在七年级爱德思统计课程中，学生通过解决真实场景问题来培养核心数据处理技能。本案例分析将带你逐步完成一个实际调查，从设计问卷到解读结果。你将练习收集数据、制作表格和图表、计算平均数和极差，并用这些结果得出有意义的结论。让我们一起深入一个基于学校食堂调查的完整统计项目。

1. Introduction to the Case Study: School Canteen Survey | 案例介绍：学校食堂调查

The school wants to improve its canteen menu. As a student statistician, you have been asked to find out which main dishes and drinks are most popular among Year 7 pupils. You will also investigate how much students typically spend per day and whether boys and girls have different preferences. This practical exercise mirrors the type of investigation you might encounter in the Edexcel statistics curriculum.

学校希望改善食堂菜单。作为一名学生统计员，你的任务是调查七年级学生中最受欢迎的主菜和饮品。你还需要了解学生通常每天花费多少钱，以及男生和女生的偏好是否存在差异。这项实战练习反映了爱德思统计课程中你可能遇到的调查类型。

2. Designing a Questionnaire | 设计调查问卷

A good statistical investigation starts with a clear question or hypothesis. We want to answer: ‘What is the most popular main dish in the canteen?’ and ‘Is there a difference in spending between boys and girls?’ To collect this data, we need a simple, unbiased questionnaire. The questions must be easy to understand and give us categorical data (favourite dish, drink) and numerical data (amount spent). Here is an example of the survey form we used.

一项好的统计调查始于一个明确的问题或假设。我们想回答：“食堂里最受欢迎的主菜是什么？”以及“男生和女生的花费是否存在差异？”为了收集这些数据，我们需要一份简单、无偏见的问卷。问题必须易于理解，并为我们提供分类数据（最喜欢的主菜、饮品）和数值数据（花费金额）。以下是我们使用的调查表示例。

The questionnaire included:

• Gender: Boy / Girl
• Favourite main dish: Pasta, Pizza, Chicken wrap, Salad, Fish and chips
• Favourite drink: Water, Juice, Fizzy drink, Smoothie
• Amount spent today (in £): ___

调查问卷包括：

• 性别：男 / 女
• 最喜欢的主菜：意面、披萨、鸡肉卷、沙拉、炸鱼薯条
• 最喜欢的饮品：水、果汁、碳酸饮料、思慕雪
• 今天的花费（英镑）：___

3. Collecting Data: Tally Charts and Frequency Tables | 数据收集：计数表和频数表

We surveyed 60 Year 7 students (30 boys and 30 girls). The raw data was recorded on paper. To organise it, we used tally marks for the categorical variables. A tally chart uses groups of five marks, where the fifth mark crosses the previous four to make counting easy. After tallying, we counted the frequencies and created a frequency table. Here is the result for favourite main dish.

我们调查了60名七年级学生（30名男生和30名女生）。原始数据记录在纸上。为了整理这些数据，我们对分类变量使用了计数符号。计数表采用五个一组标记，第五个标记划掉前四个，以便轻松计数。完成计数后，我们统计频数并创建了频数表。以下是最喜欢主菜的结果。

Notice that the total frequency is 60, which matches the number of students surveyed. This is an important check. We can already see that Fish and chips has the highest frequency (20), while Salad has the lowest (6). These frequencies help us answer our first question.

请注意，总频数为60，这与接受调查的学生人数相符。这是一次重要的核对。我们已经可以看到炸鱼薯条的频数最高（20），而沙拉的频数最低（6）。这些频数有助于回答我们的第一个问题。

4. Organising Data: Grouped Frequency Tables for Spending | 数据整理：花费的分组频数表

The ‘amount spent’ is numerical data. When the values vary over a wide range, it is useful to group them into class intervals. We recorded how much each student spent (in £) and decided to use equal class intervals of width 0.50, starting from £1.50. The grouped frequency table helps us see patterns without listing every single value.

“花费金额”属于数值数据。当数值变化范围较大时，将它们归入组距会有帮助。我们记录了每位学生的花费（以英镑计），并决定使用等宽组距0.50，从1.50英镑开始。分组频数表能帮助我们在不列出每个值的情况下看清分布规律。

The modal class is £2.50 – £2.99, with the highest frequency of 18 students. This tells us the most common spending bracket. Grouping does lose exact values, but it makes the overall distribution much clearer.

众数组是2.50 – 2.99英镑，频数最高为18名学生。这告诉了我们最常见的消费区间。分组确实会丢失具体数值，但它让整体分布变得清晰得多。

5. Visualising Data: Bar Charts and Pictograms | 数据可视化：条形图和象形图

The frequency table for main dishes can be displayed using a bar chart. Each category is on the horizontal axis, and frequency is on the vertical axis. Bars are drawn with equal width, and gaps between them emphasise that the data is categorical, not continuous. We drew a bar chart for favourite main dishes. It showed that Fish and chips has the tallest bar, confirming it is the most popular.

主菜的频数表可以用条形图来呈现。每个类别位于横轴上，频数在纵轴上。条形等宽绘制，它们之间的间隔强调数据是分类数据而非连续数据。我们绘制了最喜欢主菜的条形图。图中显示炸鱼薯条的条形最高，证实了它是最受欢迎的。

We also created a pictogram for favourite drinks using a key: each drink icon represents 2 students. Pictograms are a visual way to compare frequencies and are particularly useful for presenting data to a younger audience. The pictogram revealed that Water was chosen by 22 students, Juice by 18, Fizzy drink by 14, and Smoothie by 6. So the most popular drink overall was Water.

我们还用了一个图例来制作最喜欢饮品的象形图：每个饮料图标代表2名学生。象形图是一种直观比较频数的方法，特别适合向更年幼的观众展示数据。象形图显示，选择水的有22名学生，果汁18名，碳酸饮料14名，思慕雪6名。因此总体上最受欢迎的饮品是水。

更多咨询请联系16621398022（同微信）