Measured/ manipulated or both
hair colour
both
What type of variable would separate answers into A, B, C, D (AKA multiple choice exams)
Nominal - they are a categorical variable where the letter has no meaning to order
Describe as many characteristics of a pie chart
"slices of a whole"
"visual proportions"
used for categorical data
downside: they can be misleading and misused - such that all the parts do not add up to 100
103
(102.5-103.5)
Multiple peaks
Bi modal
Cell phone use
Both
Movies from most to least favourite
This represents an Ordinal scale because they are ordered from "best" to "worst" in terms of ranking. Interval is not known in an ordinal variable - meaning that from the best movie to the worst movie there are not exactly 9 points separating them
Describe the bar graph
- categorical and continuous variable on axis (ex. gender and memory score)
- easy to read and look at/ understand
63
(62.5-63.5)
Skewed to the right -->
Positive skew
extraversion
Measured
What type of variable is height or weight and why?
Ratio Scale - both weight and height are a continuous variable, yet they have a true variable (meaning the absence of something) in this case zero kg means zero weight and zero cm means zero height.
Box Plot
Median - middle bar (Q2)
first quartile (25th percentile)
third quartile (75th percentile)
IQR - Q3-Q1
15
(14.5-15.5)
Skewed to the left
negative skew (remember think negative numbers are to the left on the graph)
your reading ability
measured
Number of exams questions answered correctly is a _____ type of variable
Ratio - because there is an equal distance between 5 questions right and 10, and 20-30 correct answers and there is a true zero
Histrogram
for continuous data
starts with a frequency distribution
No gaps
24
(23.5-24.5)
Why is a bell curve a normal distribution?
because all the scores are normally distributed (meaning half of the scores fall on either side of the midpoint)
has a single peak (unimodal)
two tails that extend equally
forms a bell curve
You will use this curve a lot this semester!!!
attend public or private school
measured/ both
Name an interval variable that is NOT temperature
- PH scales
- IQ scores (there is no true zero) and there is a meaningful difference
Frequency Polygon
continuous data
smooth curve
uses midpoint - because this best represents the category
allows us to take scores that are in between
212.5
212-213
Bonus point question! Can anyone describe what either positive kurtosis, or negative kurtosis
positive - leptokurtic (think more squished distribution)
negative - platykurtic (think a plateau)