Week 2 Flashcards
Population
a complete set if things we could observe e.g. prison inmates
Parameter
the thing we want too know about that population e.g. percent with brain injury
Population parameter
a number that describes something about an entire population
Why can’t we directly measure our population parameter?
it would require you to take measurements from the entire population
impractical - time and money
theoretically impossible - population is infinite, its constantly changing
Sample
a group of population individuals selected from the population to be observed
Sample statistic
the thing we measure in our sample
helps us to make an inference about the population parameter
Sampling errors
no two samples selected will be the exact same
the sample statistic will vary
the underlying population parameter stays the same
Sampling distribution
a sample statistic repeated will form a sampling distribution
Why is it better to use larger samples?
larger samples will give you a better estimate of the true population parameter
minimises sample errors and makes sample statistic more accurate as sampling distributions are wider for smaller samples
Bias sampling
Individuals in a population don’t have the same probability of being selected
therefore sample doesn’t actually represent the population from which it is drawn
random sampling
every member of the population has an equal chance of being selected
allows us to make inferences
representative sample
a sample from the population that accurately reflects all individuals
What will happen if we have an unrepresentative sample
we will end up with bias statistics
Stratified sampling
overcomes sampling bias
defining sub-groups from the intended population, then pool those sub-samples, and select a certain number for the final sample
Self-selection bias
individuals choose whether they wish to participate or not
Consequentialist ethics
whether an act is right or wrong depends on the results
actions should maximise good consequences
Deontological ethics
what people do. the actions themselves are right or wrong according to moral rules
Virtue ethics
a right act is the action a virtuous person would do in the same circumstance
Minimal risk
a study doesn’t pose greater risk that what’s experienced in everyday life
What if the risk is greater than minimal risk?
participants are deemed at risk and safeguards need to be put in place
what are the 4 ethical principles?
respect
responsibility
competence
integrity
Respect
of a persons dignity
must consider: privacy, confidentiality, consent, right to withdraw, impacts on the wider environment
Competence
the ability to provide services to a required professional standard
must consider: caution in making claims
Responsibility
for what is within their power and control
must consider: debrief, continually of care, competing duties
Integrity
being honest, truthful and consistent in ones actions
must consider: objectiveness, unbiased, fairness, professionalism
what are the 5 steps to risk assessment?
- identify the risks
- establish potential harms and people potentially affected
- evaluate the scale of risk and develop control measures
- document findings in protocol
- assess effectiveness by considering the magnitude of potential harm and likelihood of it occurring
When might having a larger sample not be better?
if a sample is not representative, then the larger it gets the more bias it becomes
mistaken inferences will be made with high confidence
