Inferential Statistics Flashcards
There is something going on
Alternative
There is nothing going on
Null
2 competing claims are independent
Null
2 competing claims are dependent
Alternative
Can we “accept the null hypothesis”?
No
Can we “fail to reject the null hypothesis”?
Yes
What is unusual? Null or alternative?
Alternative
The null hypothesis represents the
Status quo
Alternative hypothesis represents our
Research question
If two variables data happen DUE TO CHANCE, they are
Independent
If two variables change DUE TO AN ACTUAL EFFECT ON ONE, this is
Dependent
Probability of observing an outcome at least as extreme as the one observed in the original data is the
P-value
If the p value is low, the N o should _______ in favor of the alternative
Go
What are the four N of null?
Nothing new
Nothing different
Nothing changed
Negation of the research question
If the Null is true, then
Test it
If the null is rejected
Consider alternative
Alternative is known as ACU
Assumption
Claim
Unknown
What is the SAG of null
Status quo
Assumption
Given
Ho is always ______________ Ha
In opposition
Which one contains equality?
Ho / Null
Which one does not contain equality?
Ha / alternative
What are three possibilities in Ho and Ha
Ho = Ho _
Ha # Ha > Ha <
We can ___________ or _____________ the null hypothesis or Ho.
Reject ; fail to reject
If we reject the Ho, it means that the
Ha is supported by data
If we fail to reject the the Ho, it follows that the Ho is “true”. True or false?
False
If we fail to reject Ho, Ho _____________ as true.
Does not follow
Words to avoid TCP
Truth
Certain
Prove
Words to Prefer
Indicate
Support
Infer
In a random process, we know ____________________, but we don’t know ____________________.
What outcomes could happen; which particular outcome will happen
Examples of random process
Coin toss
Die roll
Ipod shuffle
Stock market
probability of event A is
P (A)
Probability value should be
Less than 1 greater than 0
If we observed the random process an infinite number of times, the probability of an outcome is
The proportion of times the outcome would occur
Probability is a subjective degree of belief
Bayesian interpretation
The Bayesian interpretation is largely popularized by
Revolutionary advance in computational technology and methods during the last twenty years
As more observations are collected, the proportion of occurrences with a particular outcome converges to the probability of that outcome
Law of large numbers
Common misunderstanding of law of large numbers
Gamblers fallacy (law of averages)..there is no memory
Synonym for disjoint events
Mutually exclusive
Disjoint events
Cannot happen at the same time
Example of disjoint events
Single toss coin
Subject pass or fail
Single card from a deck
Events that can happen at the same time
Non-disjoint
The outcome of a single toss coin is
Disjoint outcomes
Grade A in stat and eco
Non disjoint
Formula for disjoint probability
P(A and B) = 0
Formula for non-disjoint probability
P(A and B) not equal to 0
If knowing the outcome of one provides no useful information about the other’s outcome
Independence
P (A|B) = P(A), then A and B are ________________.
Independent
If A and B are independent, P(A and B) = P(A) x (B).apply. Two tails in a row
1/4
