Scientific Processes Flashcards
What are behavioural categories as an observational design?
- When a target behaviour is broken up into components that are observable & measureable
- (operationalisation)
sometimes referred to as a behaviour checklist
What is time sampling?
- Where the researcher records all behaviours for a set time frame at a set point
e.g. They record each participant behaviour for 20 seconds every 15 minutes over a 2 hour observation
What are the pros & cons of time sampling?
Pros:
- Time sampling allows the researcher flexibility to record behaviour & has the opportunity to record unexpected behaviours
Cons:
- However it can also miss behaviours that do not happen within the set time
What are the various different methods of sampling?
- Random Sampling
- Stratified Sampling
- Opportunity Sampling
- Volunteer Sampling
- Systematic Sampling
What is meant by the ‘population’ when referring to sampling?
The population is the group of people from whom the sample is drawn
What does it mean when a sample is representative?
- If sample is representive then you can generalise the results of your study to the wider population
What is random sampling?
- A sample in which every member of the population has an equal chance of being chosen
- Involves identifying everyone in the target population and selecting the number of participants you need in way that gives everyone in the population an equal chance of being picked
What random sampling methods are there?
The ‘lottery method’:
* Create random number table
* Allocate each memeber of the population a random number and then choose the participants using the computer
What are the advantages and disadvantages of random sampling?
Advantages:
* More likely to be representive of whole population
* Potentially unbiased
Disadvantages:
* Time consuming & difficult- complete list of traget population may be extremely difficult to contain
* Expensive
What is opportunity sampling?
- Consists of taking the sample from people who are avaliable at the time
- The study is carried out and fit the criteria you are looking for
What are the advantages of opportuinity sampling?
Much less costly in terms of time and money than other methods (e.g. random sampling as you do not need to go out and get a full list of the population)
What are the disadvantages of opportunity sampling?
Opportunity sampling suffers from two forms of bias:
* Firstly, sample is unreprensatitive of target population as it is drawn from a very specific area in a town so findings cannot be generalsied to target population
- Secondly, the researcher has complete control over the selection of participants and, for instance, ,ay avoid people they do not like the look of (researcher bias)
What is volunteer sampling?
(Also called self-selected sampling) consists of participants becoming part of a study because they volunteer when asked or in response to an advert
What are the advantages and disadvantages of volunteer sampling?
Advantages:
* Easy, requires minimal input from the researcher (they come up to you)
* Less time consuming than other forms of sampling
* Researcher end up with volunteers who are more engaged, more so than someone who was stopped in the street
Disadvantages:
* Volunteer bias- Asking for volunteers may attract a certain ‘profile’ of person, that is, one who is curious and more likely to try and please the researcher (which might then affect how findings can be generalised)
