Week One Flashcards
(17 cards)
What is a sample?
A selection of a population we wish to study
What types of surveys are there?
Questionnaire, interview, one-off, longitudinal and repeated cross sectional
Frequency distribution
A range of values which fall into different intervals
Population parameters
Numbers that characterise how a variable is distributed across a population
Sample statistics
Numbers which characterise how a variable is distributed across a sample:
- mean
- mode
- median
- range
Mean
The average of the numbers (cases) - add all data and divide by n
Mode
The most frequently occurring number
Median
The middle number in the data set.
Range
The maximum value minus the minimum value.
Measures of central tendency
- mean
- median
- standard deviation
- model values (frequencies)
What are descriptive statistics?
A way of ordering summarising and exploring the data you have without making any statistical inference.
What is discrete data?
Values that can be counted as distinct and separate categories and can only take particular forms. E.g number of people.
What is continuous data?
Data that can take any value within a range. E.g height.
What is categorical or nominal data?
Data that is grouped but not ranked. E.g ethnicity or gender.
What is ordinal data?
Data that can be ranked or has a ranking but cannot be measured. E.g preference.
What is an interval measure?
Zero is arbitrary (temperature)
What is a ratio measure?
Zero is meaningful (height)
