Scales of Measurement
Formulas
Central Frequencies
Measures of Variability
Descriptive Statistics
100
A survey that asks, what is your gender?
What is nominal
100
Q1-1.5xIQR
Q3+1.5xIQR
These are used to find
What is lower and upper boundaries
100
The three types of central frequencies
What is Mode, Median, Mean
100
The average distance from the mean
What is standard deviation
100
A specific characteristic of elements in data
What is a variable
200
Give a rate from 1-10 on how difficult the problem is
What is ordinal
200
s/x
What is coefficient of variance
200
Sum of weighted data values/ Sum of the weights
What is weighted mean
200
Q3-Q1
What is the interquartile range.
200
Largest data value-Smallest data value/ Number of classes
What is approximate class width
300
Has a meaningful zero
What is ratio
300
What is the quartile formula
300
The shape in general(not always) if the data shows
Mean>Median>Mode
What is positively skewed
300
It is very sensitive to extreme values or scores
What is range
300
The difference between cross-sectional and time-series data
What is cross-sectional is data at (approximately) one point of time and time-series is data over a period of time
400
It is always numeric
What is interval
400
What is population variance
400
The only central tendency measure at the nominal level
What is mode
400
Steps to calculate percentiles, and show example
1. Order or rank the values first
2. Use the quartile formula to determine the position
3. Using position, determine the percentile value.
400
If extreme values go to the left the distribution is
Negatively skewed
500
Indicates the most appropriate data summarization and statistical analyses
What are scales of measurement
500
What is sample variance
500
Only used for quantitative data
What is mean
500
Used to compare distributions with different units or to compare distributions with the same units but very different means
What is coefficient of variance
500
Shows the total number of items with values less than or equal to the upper limit of each class.
What is a cumulative frequency distribution