unit 3 - Data, Sampling, research & hypothesis Flashcards
What is a target population
The group of people from whom the sample is drawn from.
Why do we obtain a sample
Because the target population is too large
Why should a sample be carefully selected
Because it needs to be representative
What is qualitative data
Words, descriptions, colours, observations.
No numbers
What is quantitative
Uses quantities, values or counts
What is an example of qualitative research
Interviews
Focus groups
Observations
What are examples of quantitative
Closed questionnaires
Laboratory experiments
Epidemiological (medicine)
Positives of using interviews of focus groups
-collects detailed information from a small amount of people
-produces rich and insightful information
-great for asking why or how questions
Negatives of using interviews and focus groups
-requires a lot of time for data collection
-results in a lot of data which is time consuming to analyse
-small volume of people
Advantages of observations
Good for finding out peoples behaviour
Disadvantages of observations
-need to be approached with awateness because people being observed may change how they act
-does not investigate views
Advantages of surveys
-great for retrieving factual data from “what” questions
-can be completed anonymously, so are good for
investigating sensitive subjects that people may not want
to talk about
-offer a relatively quick way of gathering data from a lot of
people at once
-provide data that is fairly easy to categorise and analyse
-use mainly closed questions, with responses as scale
Disadvantages of surveys
-aren’t good for getting answers to open questions, as
people may not want to write much
-are of limited help in understanding more complex
issues
-aren’t suitable for getting information from very
young children
What are the types of sampling
Random
•Systematic
•Stratified
•Snowball
•Opportunity
•Self-selected
What do you need to take into account when analysing
The ability to recruit suitable participants in your study
*representative
What is sampling
The ability to recruit suitable participants in your study
*representative
If your sample is representative, what can you do with your results
Generalise them to the wider population
What is random sampling
Numbering each individual in a population and then using a random generator to select the sample
Systematic
Numbering each individual
1,2,3 and then selecting one category
What is stratified sampling
Classify the whole population into categories, then choose a sample that is in the same
proportion as the population
What is snowball sampling
One person gets 2 people, they get 2 more people, they each get 2 more people and so on
What is opportunity sampling
Uses people from target population available at the time and
willing to take part. It is based on convenience.
What is self selected sampling
People volunteering to become part for to advertising
What is the main thing you should take into account when choosing sampling method
It must eliminate bias without discrimination
What are the 4 areas you have to attend too when processing data
- Statistical methods
- Conclusions
- Evaluation of procedure
- Mathematical notation
What are the 3 main statistical methods
Mean
Mode
Median
What is measures of dispersion
How spread out the data is from the average you calculated
*How varied the data set is
What does continuous data mean in terms of a graph
Every piece of data will have a plot
-you can find the mean
How can you find the measure if dispersion
Standard deviation
What is skewed distribution
When the bell curve of normal distribution is shifted
What is significance
Measure of how different the data is that you expected
Name 2 types of parametric tests
- T test
- standard deviation
What is standard deviation
Compares the data spread to the mean
What is the T test
Compares 2 means from 2 different data sets to see if there is a significant difference
What type of data uses the T test
Continuous
What is the chi squared test
Tests the significance of the difference between observed and expected results between categories
Points for evaluation of the ethics of research
- Social/scientific value
- Care and protection of participants
- Confidentiality
- Informed consent
- Working with vulnerable individuals
what is descriptive research
attempting to find patterns, ideas or hypotheses through the gathering of baseline/preliminary information
what is exploratory research
describes circumstances or concepts as it exists, used to obtain data on the characteristics of a particular issue
what is analytical research
attempts are made to explain why or how something is happening
what is predictive research
attempts to forecast the likelihood of a similar situation occurring through generalisation
what is a null hypothesis
the hypothesis of no significant difference
what is the rule for accepting or rejecting a null hypothesis
you reject the null when the critical value is equal too or above the value calculated
what is directional hypothesis
it predicts the direction of the results
what is non directional hypothesis
predicts there will be a difference but does not predict the direction
