Lecture 3 Flashcards
(23 cards)
What is spurious correlation?
When both sets of data have a correlation but not when on the same y-axis
How do we find causality?
From an experiment
What is the purpose of an experiment?
To test a hypothesis and you often manipulate something.
When preforming an experiment why would you need to change a variable?
To see if the other variable changes as well to see if they are directly connected
What is the independent variable?
The manipulated variable
What is the dependent variable?
It is the measured outcome that is dependent on the independent variable
What is random assignment?
When you take the decision out of your hands. Flip a coin.
What is the experimenter expectancy effect?
To prevent biased measurements the person making the measurements should not know the expected outcome
How can we help eliminate experimenter expectancy effect?
“Blinded” experiments
Once you have preformed an experiment is the result a correlation or causality?
Experiments lead to a conclusion, therefore it is not longer a correlation it is a causality because we have proved that they are directly connected.
What is a placebo?
When you have a control group and then a placebo control group, you give a group a placebo which is a fake, for example a sugar pill. They must be blinded as to if they have the placebo or the real thing.
What is a single blind experiment?
You don’t tell the participants what they are getting
What is a double blind experiment?
You don’t tell the participants what they are getting and the researchers are not told who took what.
What are confounding variables?
When you manipulate something and your manipulation manipulates two things at once without you knowing.
When you have a confounding variable can you confirm causality?
No you can not because you can’t be sure that your results are from what you manipulated, it could be from the second thing you accidentally manipulated
What is the Mozart Effect?
Study that showed listening to Mozart increased people’s intelligence. It was later found it wasn’t Mozart it was just happy music which increased people’s moods. Increased moods was the confounding variable.
How do we quantitatively describe groups?
We measure the groups central tendency and then measure the variability within the group
What are the three measures of central tendency?
Mean, median, and mode.
What are the measures of variability?
Range, standard deviation, and normal distribution
What is the range when talking about variability?
The maximum spread of samples from the smallest to largest values
What is the standard deviation when talking about variability?
A measure of the average distance between scores in a sample and the mean. How much each number varies from the mathematical average.
Is a large standard deviation good or bad?
It is bad. When trying to make conclusions from data we want a small standard deviation.
What is normal distribution when talking about variability?
When there is a tendency for most people to be in the middle of the group.
