Vocabulary
_________ is an object described in a set of data. Can be people, animals, or things
Individual
Does "time" fall under discrete or continuous quantitative variables?
Continuous
What are the 3 types of shapes that a distribution can have?
What is the difference between x-bar and Mu?
x-bar: mean of sample
Mu: mean of population
What are the two outlier rules called?
1.5 x IQR rule
2 Standard Deviations Rule
_________ is a characteristic that changes from one individual to another.
Variable
What type of distribution shape has the bulk of its data on the right and decreases to the left?
Skewed Left
What would be considered an outlier in a distribution?
Gaps and Clusters
How do you find the mean if there are even numbers?
Find the mean of the two middle values
How do you use the 1.5 x IQR rule?
1.5 (IQR)
Q1 - 1.5 (IQR)
Q3 + 1.5 (IQR)
A variable that takes on numerical values for a measured or counted quantity
Quantitative variable
1|2469
2|1588
3|3356
Key: 0|1=1
What is the value of the 4 on the right side of the 1?
14
What is the relationship between mean and median?
If a distribution is ROUGHLY SYMMETRIC, the mean and median are the same
SKEWED RIGHT: mean is higher than median
SKEWED LEFT: mean is lower than median
How do you find high and low outliers from the 2 SD rule?
LOW: mean - 2(Sx)
HIGH: mean + 2(Sx)
A variable that takes on values that are category names or group labels
Categorical variable
What category of "socs" does stating the range fall into?
Spread
_______ is how similar/varied the set of values is for a variable
Spread
What is standard deviation and how do you interpret it?
measures the average distance of the observations from their mean.
On average the values in the distribution of _____ vary from the mean by _____ units.
How do you know when to use which outlier rule?
2SD: wider interval, fewer outliers
1.5 IQR: narrower intervals, more outliers
What are the two types of Quantitative variables?
Discrete and Continuous
How do you find the Interquartile Range?
Q3-Q1
What does the second "C" in "socs" stand for and why is it needed?
Varience
What is the best measure of center and spread for a symmetric distribution? Skewed distributions?
SYMMETRIC: mean, SD
SKEWED: median, IQR