Cover lesson · Digital Technology · Year 10 · Intermediate

Using survey statistics to plan a website

LNF: Numeracy → Learning that statistics represent data and that probability models chance helps us make informed inferences and decisions → Interpreting data

Name: Class: Date:

Cover teacher: you need no subject knowledge

What this practises: interpreting data in Digital Technology. Pupils use percentages, the mean, median, mode and range to summarise an invented visitor survey, spot an outlier and decide which average to trust, compare groups, and turn the statistics into design decisions for a website. This is the skill in GCSE Digital Technology Unit 2, Section 2.1.2: “descriptive data analytics uses statistical summaries to identify patterns, trends, and relationships within the data”. Practice only with an invented client, not NEA work. Pupils must not work on their own Unit 2 brief in this lesson.

Print: this sheet, one per pupil, and the stimulus sheet “Canolfan Antur Cwm Nant: the visitor survey”, one between two. Calculators are allowed. No computers are needed; if you are in a computer room, pupils who finish early can check their answers with the CSV file in a spreadsheet.

Run: 6 min read the survey and do Step 1 · 10 min Step 2, minutes to book · 8 min Step 3, the outlier · 10 min Step 4, comparing devices · 6 min Step 5, features · 12 min Step 6, design decisions · 3 min success criteria. Total 55 minutes.

Collect: this sheet. The worked example has every answer. Checkpoints: 60% booked on a phone; the median time to book is 9 minutes; phone users rate the website 3.75 out of 10 on average, laptop users 7.4.

What you are doing

Llinos wants a new website for her adventure centre, based on evidence. You have 20 survey answers. You will summarise them with statistics, decide which numbers to trust, and then write design decisions that each rest on a number. Show your working so Llinos can check it.

Step 1: which devices do visitors use?

Count the devices in the survey. Each person is 5% of 20.

DeviceTallyFrequencyPercentage
Phone
Tablet
Laptop
Total

Step 2: how long does booking take?

(a) Write the 20 values for minutes to book in order, smallest first.

(b) Work out each statistic. Show your working.

StatisticWorkingAnswer
Mean
Median
Mode
Range

Step 3: the outlier

(a) Which value is an outlier? Read the comments column: why is it so big?

(b) Work out the mean and the range again without the outlier. Give the mean to 2 decimal places.

(c) Which average best describes a typical booking time: the mean with the outlier, or the median? Explain why.

(d) Should Llinos ignore the outlier completely? Give a reason.

Step 4: comparing devices

Find the mean website rating and the mean minutes to book for each device. For phone users, leave out the outlier when you work out the minutes (so divide by 11). Give answers to 2 decimal places where needed.

DeviceMean rating (working)Mean ratingMean minutes (working)Mean minutes
Phone
Tablet
Laptop

(b) Describe the pattern in one or two sentences, using numbers. What does it suggest about the current website?

Step 5: what do visitors want?

Most wanted featureFrequencyPercentage
Online booking
Prices
Photos and videos
Weather

Step 6: design decisions for Llinos

(a) Write three design decisions for the new website. Each one must be backed by a statistic from Steps 1 to 5. Use the frame: “The new website should… because… (statistic).”

(b) Give two limitations of this survey. How might each one make the conclusions wrong?

Step by step

  1. 6 min Read the survey. Step 1: devices and percentages.
  2. 10 min Step 2: mean, median, mode and range of minutes to book.
  3. 8 min Step 3: the outlier and which average to trust.
  4. 10 min Step 4: compare the three devices.
  5. 6 min Step 5: most wanted features.
  6. 12 min Step 6: three design decisions and two limitations.
  7. 3 min Tick the success criteria you have met.

Success criteria

If you finish early