1. Start with a question
Does a heavier penguin always have a longer bill?
We can use several measurements to check that idea.
Slide 1 of 5
2. Choose the records
This example uses six complete measurement records per species: 18 penguins in total.
The selection follows the source file order. It is not a random sample.
3. Compare body mass
Mean mass in the selection:
- Adelie: 3587.5 g
- Chinstrap: 3708.3 g
- Gentoo: 5050.0 g
| Species | Mean mass (g) |
|---|---|
| Adelie | 3587.5 |
| Chinstrap | 3708.3 |
| Gentoo | 5050.0 |
4. Check another measurement
Chinstrap row 281 has a mass of 3725 g and bill length of 52.7 mm.
Gentoo row 154 has a mass of 5700 g and bill length of 50.0 mm.
The heavier record has a shorter bill.
| Record | Mass (g) | Bill (mm) |
|---|---|---|
| Chinstrap 281 | 3725 | 52.7 |
| Gentoo 154 | 5700 | 50.0 |
5. Keep the conclusion limited
More mass does not guarantee a longer bill in these records.
Next, use the full dataset and compare by sex, year, and island. A small selected sample cannot answer every question.