Here is one of the questions from Tom's study. Write down two different problems with this question.
Question: "How old are you? Tick a box: [ ] under 21 [ ] 21-50 [ ] 51-60 [ ] 61-70"

There are several problems with this question design: 1. **Problem 1: The response boxes are not exhaustive.** The options only go up to age 70. There is no option for anyone aged 71 or older, so they cannot answer the question. All possible ages should be included. 2. **Problem 2: The groups have unequal widths.** The "under 21" group is 21 years wide. The "21-50" group covers a 30-year range. The "51-60" group covers a 10-year range, and "61-70" covers a 10-year range. These unequal class intervals make it difficult to analyse the data fairly or to represent it in a histogram. (Note: The boxes are mutually exclusive. "under 21" means up to 20. So someone who is 21 would tick the "21-50" box. So overlapping boxes is not an error here).