Variables
How is the dependent variable different to the independent variable?
The dependent variable is the property that is MEASURED, while the independent variable is the property that gets manipulated or varied by the experimenter
What are the 3 measures of central tendency?
Mean, median, mode
How long does information stay in your short term memory
12-30s
What is the dependent variable in this graph?
Number of words remembered
Qualitative v quantitative data
Qualitative data refers to descriptions of characteristics while quantitative data refers to measurements (numerical info)
Identify the IV and DV:
Primary school children who watch violent cartoons will have more nightmares than those who watch humorous cartoons
IV: Type of cartoon watched
DV: Number of nightmares
If the correlation co-efficient is -0.9, is it:
a. weak positive
b. weak negative
c. strong positive
d. strong negative
strong negative
How many pieces of information can we store in our short term memory?
5-9 pieces
What is the relationship in this graph?
As you progress through the order of words in the sequence, the number of words remembered decreases
How is the experimental group different to the control group?
Experimental group is exposed to the IV while the control group is not
What are extraneous variables?
A variable other than the IV that could cause changes to the value of the DV.
What does a trendline on a graph show?
How strongly two variables are related to each other
What happens to the information after the 12-30s it spends in our short term memory?
Gets lost or transferred to our long term memory
What is the trend in this graph?
Is it positive or negative?
As the temperature increases, the number of sales increases
Positive
What is the benefit of random sampling?
Reduced bias
Identify the IV and DV:
Rest periods taken during examinations will lead to decreased state anxiety in students during their final exams
IV: Rest periods
DV: Amount of anxiety experienced
What does it mean if a graph has a positive correlation?
that both variables change in the same direction - as one increases, so does the other
How can you ensure a short term memory test is valid?
Ensure it is kept within the 30s time frame
What is the trend in this graph?
Is it positive or negative?
As the independent variable increases, the dependent variable decreases
Negative
What is the definition of psychology?
Psychology is the scientific investigation of mental processes (thinking, remembering and feeling) and behaviour
For drivers, an increase in blood alcohol levels will cause a decrease in reaction speed
Identify 2 extraneous variables for this experiment
Time of day, existing reaction speed of participants, task performed, previous exposure to the task
What does it mean if an experiment is reliable?
the measuring instrument is consistent
What strength correlation does this graph have? How do you know this?
Strong because the r squared value is 0.9 and the strongest value is 1.
On a graph, does the dependent or independent variable go on the y axis?
dependent