Qualitative, quantitative, continuous, discrete, primary and secondary data
Write one sentence. Be ready to improve it.
Describes qualities, categories, appearances or observations using words.
Examples: colour change, cloudy solution, type of organism, smell, texture.
Uses numbers from counts or measurements.
Examples: 23°C, 14 colonies, 6.2 cm, pH 7.4, mass 1.8 g.
Measured data that can take any value within a range.
Examples: height, temperature, time, mass, volume, concentration.
Counted or category data with separate values.
Examples: number of leaves, blood group, number of colonies, shoe size category.
Note: some category data can be coded with numbers, but that does not automatically make it continuous.
Information noticed using senses or instruments. Often qualitative, but can be recorded systematically.
Example: leaf colour, colony shape, presence of bubbles.
Numerical values taken using equipment and units.
Example: mass in g, volume in cm³, temperature in °C, time in s.
Data you collect yourself for your own investigation.
Example: measuring enzyme reaction rate in your practical.
Data collected by someone else that you use to inform your own work.
Example: using published climate data, research papers, databases or previous class results.
| Data type | Advantages | Disadvantages |
|---|---|---|
| Primary | Specific to your aim; you control method and variables; you know how it was collected. | Can be slow, expensive or limited; sample size may be small; may contain errors from your method. |
| Secondary | Can provide large samples; saves time; allows comparison, replication and wider context. | May not perfectly match your aim; method may be unclear; could be outdated or biased. |
Use for categories or discrete groups.
Categories
Use when showing continuous change, often over time.
Time / continuous variable
Use to look for a relationship between two continuous variables.
Relationship?
Create a glossary for:
A student says: “Quantitative data is always better because it has numbers.”
Write a response that explains why this is not always true.
Answer each question. Your score will appear at the end.
A student investigated how different types of sugar affected yeast respiration. They measured the number of bubbles produced in one minute.
| Type of sugar | Number of bubbles per minute |
|---|---|
| Glucose | 42 |
| Fructose | 35 |
| Sucrose | 27 |
| Lactose | 8 |
Task: Draw a suitable graph to display these results.
A student investigated whether exercise duration affects heart rate. Heart rate was measured immediately after exercise.
| Exercise duration (minutes) | Heart rate (bpm) |
|---|---|
| 1 | 78 |
| 2 | 84 |
| 3 | 93 |
| 4 | 102 |
| 5 | 110 |
| 6 | 118 |
Task: Draw a suitable graph to display the relationship between the variables.