What's the mean?
3, 5, 7
5
2, 4, 4, 5, 7
4
7,3, 5
5
The number of students in a classroom.
Numerical- discrete
A survey is conducted where every single student in a school is asked about their favourite subject.
Census - survey includes everyone
8, 10, 12, 14
11
1, 3, 5, 3, 2, 6, 3
3
4, 8, 2, 10, 6
6
The colours of cars in a parking lot.
Categorical - nominal
A researcher selects a group of 50 students from a school of 500 to ask about their study habits.
Sample survey - only a portion of the population has been selected
6, 9, 7, 10, 8
8
10, 12, 10, 15, 12, 10
10
1, 11, 3, 7, 5, 9
6
The temperature readings in degrees Celsius over a week.
Numerical - Continuous
A company selects 10% of its customers to provide feedback in their survey.
Sample - a portion of the population is selected to represent the whole.
4, 15, 22, 9, 30
16
7, 8, 10, 8, 9, 9, 10, 10, 11
10
12, 20, 14, 17, 25, 22, 30
20
The ranking of players in a tennis tournament (1st, 2nd, 3rd etc)
Categorical - Ordinal
A scientist spends a day at a park counting the number of people who recycle their trash.
Observation - the data is collected by observing behaviour without directly interacting with the participants.
8, 14, 10, x
mean = 12
x = 16
14, 16, 14, 18, 16, 20, 18
14, 16
4, 8, 15, 16, 23, 42, 108, 203
19.5
The satisfaction ratings from a survey where participants rate their experience as "very satisfied," "unsatisfied" "Neutral" "satisfied" "Very Satisfied".
Categorical - ordinal
A government conducts a survey to collect information about every household in the country to gather data on income levels.
Census - the survey targets every household in the entire population.