The vocabulary of statistics
The words of a statistical study: population, sample, individual, variable, category, variable types, counts, relative frequencies and cumulative values.
- 26 cards
- 5 topics
- Free
The outline, topic by topic
Each topic is weighted the way the exam weighs it.
- Concepts
- Questions
- Sort and link
- The numbers
- Scenarios
A few cards from the deck
Population: what is it?
Show the answer
The set of individuals the study is about, for example all the students of an institute.
It is defined before anything is observed: you cannot say what a study shows without knowing whom it covers.
In a group of 120 students, 24 are 18 years old. What is the relative frequency of 18-year-olds?
- 20%
- 24%
- 5%
- 80%
Show the answer
20%
The relative frequency is the count divided by the total: 24 / 120 = 0.2, i.e. 20%. 24% mixes up count and frequency, 5% inverts the division, 80% is the share of the others.
An … is one element of the population; the … is what is observed on it, and its possible values are its categories or values.
Show the answer
An individual is one element of the population; the variable is what is observed on it, and its possible values are its categories or values.
In “each student's commuting time”, the individual is the student, the variable is the commuting time and “25 minutes” is one observed value.
Sample: what is it?
Show the answer
The subset of individuals actually observed, when you cannot or will not question everyone.
Its results hold for the whole only if it is representative: 150 students asked in the canteen do not tell everything about 1,200 students.