Intro/Chapter 1 Flashcards
Descriptive Statistics
Reducing a closed set of data into key features
Inferential Statistics
Drawing conclusions about a larger group than you have data for; generalizations
3 steps of Inferential Statistics
1) Estimating/ Creating generalization
2) Testing the hypothesis
3) Fitting to a statistical model
2 Types of Numerical Data
continuous and discrete numerical data
Continuous Numerical Data
Data in a range, e.g: time, length
Discrete Numerical Data
Counted integers
2 Types of Categorical Data
Nominal and ordinal categorical data
Nominal Categorical Data
No natural order to the categories, e.g: gender, colors
Ordinal Categorical Data
A natural order to the categories, e.g: weekdays, scales on a test
Confounding Variables
variables that varies both the independent dependent variable, making an apparent, but not valid correlation.
Population
all subjects/specimens of interest
Sample
subset of population of size ānā
Histogram
basically a bar chart that plots y as frequency
Which side does the histogram favor?
Right. [ )
IQR
Inter quartile range Q3 - Q1
Standard deviation
s = sqrt((1/(n-1))(sum(yi-y)^2))
Sample variance
s^2
Sum of differences
sum(yi-ybar)
RV - Definition and common variable
Represents a random process (X)
Realization - Definition and common variable
observed outcome of RV (x)
Probability Distribution of X
describes values that X can take and the probability of each. ( Normally a table for discreet RV)
Discrete RV - Definition and function
only certain values can be listed p(x)
Two properties of discrete RV and variables
Mean(mu) and variance(sigma^2)
Continuous RV- Definition and function
X takes values in a range, cannot list all of them. f(x)