Chapter 1: Collection of Data Flashcards
What is raw data?
Unprocessed data that just been collected and needs to be ordered, grouped, rounded, cleaned.
Define qualitative data.
Non-numerical, descriptive data such as eye/hair colour or gender.
Define quantitative data.
Numerical data that can be measured with numbers.
What is discrete data?
Data that only takes particular values, such as shoe size or number of people.
What is continuous data?
Data that can take any value, e.g. height, weight.
Define categorical data.
Data that can be sorted into non-overlapping categories, such as gender.
What is ordinal data?
Quantitative data that can be given an order or ranked on a rating scale.
What does bivariate data involve?
Measuring 2 variables, which can be qualitative or quantitative.
What is multivariate data?
Data made up of more than 2 variables.
What is the purpose of grouping data?
Makes it easier to spot patterns and quickly see how the data is distributed.
What is a primary data source?
Data that you have collected yourself or someone has collected on your behalf.
What is a secondary data source?
Data that has already been collected.
Define population in the context of data collection.
Everyone or everything that could be involved in the investigation.
What is a census?
A survey of the entire population.
What is a sample?
A smaller number from the population that you actually survey.
What is a sampling frame?
A list of all the members of the population from which the sample is chosen.
Define biased sample.
A sample that does not represent the population fairly.
What is random sampling?
Every item/person in the population has an equal chance of being selected.
What is stratified sampling?
The size of each strata in the sample is in proportion to the sizes of strata in the population.
What is systematic sampling?
Choosing items in the population at regular intervals.
Define cluster sampling.
The population is divided into natural groups, groups are chosen at random, and every member of those groups is sampled.
What is quota sampling?
Population is grouped by characteristics and a fixed amount is sampled from every group.
What is opportunity sampling?
Using the people/items that are available at the time.
Define judgement sampling.
When the researcher uses their own judgement to select a sample they think will represent the population.