A practical measure of dispersion
Statistics is a very practical field. After all, what would we know from economic publications if it wasn’t for the preparation of statistics The bigger, the better. The quartile deviation is one such practical measure. It belongs to the dispersion tool analysis – here, we are talking about the range of similarity between the studied objects and the average value.
To calculate the quartile deviation, we will need to know the values of the quartiles. They divide the population into four parts. Most methods of calculating quartiles in the population are based on the determination of the median. Obviously, medians and quartiles should be counted in an ordered series. To get the value of the quarter deviation, we calculate the value of the first and third quartiles.
Half of a half
The term from which the quartile deviation is derived is the quartile range otherwise known as the quartile spread. It is equal to the difference between the upper and lower quartiles. Exactly half of the surveyed objects fall within its range. Conversely, quartile deviation is exactly half of this range. It follows from the essence of the quartile deviation in which extreme values are not taken into account. The practical application of this measure is superior to that of the standard deviation in providing more detailed information about the variation of average results.
Undeniably, the practical application of the quartile deviation has its limitations, but which measure doesn’t have them However, it is a very useful tool as it tells us a lot about the population and its variation.
Key takeaway
Quartile deviation: A practical measure of dispersion Statistics is a very practical field. After all, what would we know from economic publications if it wasn’t for the preparation of statistics The bigger, the better. The quartile deviation is one...
When to use it?
Decide which measure is described by "Quartile deviation".
Answer check
- Decide which measure is described by "Quartile deviation".
- Check whether the result concerns position, variation, relation or error.
- Explain what "Quartile deviation" means in this dataset instead of leaving only a number.
User-focused answer
Quartile deviation: A practical measure of dispersion Statistics is a very practical field. After all, what would we know from economic publications if it wasn’t for the preparation of statistics The bigger, the better. The quartile deviation is one such practical measure. It... Use this topic when the task asks for more than a name: you must identify the condition, choose the rule and justify the result.
When this topic is actually needed
Use this topic when the task asks for more than a name: you must identify the condition, choose the rule and justify the result. Quartile deviation: data, measure and interpretation. Start with one clear definition sentence, then show the rule, and only then substitute the data.
The most common mistake is remembering the term but ignoring the condition in the task. If the answer has a unit, keep the unit with every number; if it is a language or glossary topic, show the term in a full sentence.
Complete way to work with the topic
- name the given data and the unknown
- write the definition or relationship
- test it on a simple example
- check the unit, range or sentence meaning
If the answer has a unit, keep the unit with every number; if it is a language or glossary topic, show the term in a full sentence. Start with one clear definition sentence, then show the rule, and only then substitute the data. If the answer has a unit, keep the unit with every number; if it is a language or glossary topic, show the term in a full sentence.
Worked example with commentary
Quartile deviation: Start with one clear definition sentence, then show the rule, and only then substitute the data. If the answer has a unit, keep the unit with every number; if it is a language or glossary topic, show the term in a full sentence.
| User-focused answer | What to remember |
|---|---|
| When this topic is actually needed | data, measure and interpretation |
| Mistakes that usually weaken the answer | The most common mistake is remembering the term but ignoring the condition in the task. |
| Complete way to work with the topic | If the answer has a unit, keep the unit with every number; if it is a language or glossary topic, show the term in a full sentence. |
Mistakes that usually weaken the answer
The most common mistake is remembering the term but ignoring the condition in the task. The most common mistake is remembering the term but ignoring the condition in the task. Start with one clear definition sentence, then show the rule, and only then substitute the data.
Explain the topic in your own words. Create an example that shows when the rule can be used. Name one possible mistake and correct it.
Check exercises
- Explain the topic in your own words.
- Create an example that shows when the rule can be used.
- Name one possible mistake and correct it.
What to remember: Quartile deviation. Use this topic when the task asks for more than a name: you must identify the condition, choose the rule and justify the result. Start with one clear definition sentence, then show the rule, and only then substitute the data.