Relationship Between Variables

Relationship Between Variables

can research establish cause and effect relationship? x affect y? or the opposite?

There is a correlation (connection) between eating ice cream and getting sunburn

Does it mean that we should not eat ice-cream? Does it mean eating ice-cream causes sunburn?

CORRELATION DOES NOT (ALWAYS) IMPLY CAUSATION

just because there is a correlation between eating ice cream and getting a sunburn, it doesn't mean that ice cream is the cause of sunburn!

Just because two events occured at the same time, it doesn't mean that there is a clear connection (cause & effect) between them

correlation between eating ice cream and getting a sunburn

People who regularly use sauna tend to be healthy

• Give questionnaire to measure how often they used sauna & see health report

• ask people to use sauna 2x/week and see the differences in their health in comparison before using sauna

• which one can establish cause and effect?

Multiple Choice

Which one is an experiment?

• Give questionnaire to measure how often they used sauna & see health report

• ask people to use sauna 2x/week and see the differences in their health in comparison before using sauna

Multiple Choice

Which one can establish cause and effect relationship?

• Give questionnaire to measure how often they used sauna & see health report

• ask people to use sauna 2x/week and see the differences in their health in comparison before using sauna

• Give questionnaire to measure how often they used sauna & see health report (correlational study)

• ask people to use sauna 2x/week and see the differences in their health in comparison before using sauna (experiment)

Experiment can establish cause and effect

Correlational study cannot establish cause and effect

Watching K-Drama and sadness ...

experiment vs correlational study

Nature of experiment

• independent variable (watching k-dramas) is manipulated to see its effect on the dependent variable (sadness)

• ask people to watch k-drama once a week for 1 year and test them using psychological instruments

• one group watch k-drama (experimental group); other group watch other genre (control group). See which group tend to be more sad ...

• we can know that k-drama is the one that affects sadness and not the other way around

Nature of correlational study

• give questionnaires

• questionnaire 1: measures how often they watch k-drama

• questionnaire 2: measure how often they feel sad

• are they sad because they watched k-drama OR they watched k-drama because they are sad? Or there is no connection at all?

• cannot establish cause and effect!

How to explain it in ERQ??

• This research can establish cause and effect because the independent variable, which is ...., is manipulated in order to see its effect on the dependent variable, which is ......

• The research cannot establish cause and effect because none of the variables, which are ..... and ...., are manipulated, so the connection between them are not clear.

Evaluate these researches ONLY in terms of causal relationship

• Bandura, Ross, and Ross (1961) - p. 60

• Perry, Perry, and Rasmussen (1986) - p. 61

• Steele and Aronson (1995) - p. 64

• Rosenthal & Jacobson (1968) - P.64

• If it's a correlational study, can we evaluate in terms of ecological validity? Why?