Investigation 1 Flashcards
Title of investigation 1
A quasi experiment on age and sleep
What is the operationalised hypothesis
There will be ab increase in sleep score out of 21 on PSQI in adolescence (13-18) compared to adults (19+)
What is the null hypothesis
There will be no change in the sleep scores out of 21 on the PSQI in adolescence (13-18) in comparison to adults (19+) - any changes will be due to chance
What is the operationalised IV
Teenagers (13-18) and adults (19+)
Why is the IV operationalised in this way
Because it is a quasi experiment that needs to different age ranges
What is the operationalised DV
Pittsburg sleep quality index - out of 21
Why is the DV operationalised in this way
Because PSQI is an established measure
What are the confounding variables
-illness
-house hold noise
-medication
How to overcome the confounding variables
Discount certain scores for those who are on medication etc
Or test retest
Extraneous variables
Temperature
Time of the day
Point in the term
How are the extraneous variables overcome
Test retest
What is the methodology
1- quasi experiment
2- self-report technique
Strengths of a quasi in your research
No manipulation by the researcher
Weakness of a quasi in your research
More chance of confounding variables due to the IV being naturally occurring
Strength of a self report in your research
Quick and easy as PSQI is an already established measure
Strength of a self report in your research
Quick and easy as PSQI is an already established measure
Weakness of a self report in my research
Social desirability bias due to wanting to seem a better sleeper of researcher bias
What is the experimental design - what are the strengths/weaknesses
Independent groups
+ no chance of order effects
-participant variables
What is the sampling technique- strengths/weaknesses?
Opportunity sampling
+quicker than stratified and easier than quota
-may not be representative of the whole target population
What is the location of research - strengths/weaknesses?
Field - Notre dame
+high ecological validity - more convenient
-harder to control ev’s/cv’s
Why is it independent groups
Due to the nature of a quasi experiment, p’s can only belong to one condition
Briefly outline the procedure
Select p’s - 10 per group
Get code names by using house number and bday
Brief the study - aims, hypothesis, right to withdraw
Print PSQI and ask them to answer
Calculate scores
Descriptive statistics
Debrief
What was the significance level used and why
0.05 because its the standard probability and not for a sensitive measure e.g drug testing
What was the graphical representation used and why
Bar chart - because the data is not continuous and is ordinal + data
Descriptive statistics - what are the measure of central tendency
Mean
Median
Mode
Descriptive statistics - measures of dispersion
Range
Standard deviation
+/- of mean
+most sensitive measure and takes all values into account
-abnormalities affect the mean
+/- of mean
+most sensitive measure and takes all values into account
-abnormalities affect the mean
+/- median
+not affected by extreme scores
-not sensitive
+/- of mode
+not affected by extreme values
-may be 2 modes or 0 so not representative of data
+/- of range
+quick and easy
-sensitive to outliers
+/- of range
+quick and easy
-sensitive to outliers
+/- of standard deviation
+ shows distance from mean
- difficult and time consuming
Inferential statistics
=mann Whitney U
Independent data
Ordinal and above
Test for difference
What is the observed value
15.5
What is the critical value
5
Which hypothesis should you reject/accept
Accept the alternative hypothesis and reject the null as findings are significant
How to consider privacy - PCDRIP
Don’t ask personal question e.g sharing a room as they may be embarrassed
How to consider confidentiality - PCDRIP
No names used
P’s select own participant number
E.g house number/birth year
Not identifiable
How to consider deception
No deception - P’s know the aims from the start
How to consider right to withdraw
Brief at the start and end of
Say they can withdraw at any point during the study
48h reflection time
How to consider informed consent
Each p is given a consent form
Vulnerable children (under 16) - head teacher has given consent for them (by proxy)
How to consider protection from harm
No psychical harm
May worry about the sleep score which is unnecessary anxiety/stress
Debrief will offer help and guidance e.g website
How will I ensure internal reliability is high
Standardise instructions for all
Test p’s at same time of days
Same researcher
Same questionnaire
How to check four high external reliability
Test retest method - test p’s again in September and compare
Look for correlation - higher than 0.8 means high external reliability
How may demand characteristics affect research
We’re telling p’s the aim of the study in briefing so may act differently
How may social desirability affect research
Anonymous questionnaires so we don’t know who p’s are
- less likely to lie if they can’t be identified
What are the conclusions of the study
Alternative hypothesis was correct
There was an increase in sleep scores in adolescence compared to adults
3 ways my study could be improved
Test retest to improve external reliability and secure consistency
Split half reliability to ensure internal reliability and ensure all 21 questions measure ‘sleep’
Content validity - ask an expert to review the questionnaire and check the questions accurately measure sleep
Why do we use these descriptive statistics
Mean because we use all the values so more sensitive
Standard deviation because it is ratio data
