The three conditions for a chi-square GOF test are:
Random, Independence, and Chi-square distribution
How do you check the Random condition for a chi-square test?
Use a stratified random sample or a randomized experiment.
These two chi-square tests both start with a two-way table.
Chi square test for homogeneity as well as the test for association/independence
When completing a chi square test we test for/against the null.
We test against the null hypothesis.
What is the equation for testing Independence?
10% condition
n</= (.10)N
Chi-square statistic is used to measure what?
How far expected counts are from observed counts.
What variables do you compare when concluding a chi-square test for homogeneity.
Compare p-value and alpha.
Chi-square test for association/Independence is ran nearly identical to what other chi-square test?
Chi-square test for homogeneity.
Null hypothesis for GOF.
The claimed distributions are correct.
What criteria must be met to pass the Chi-square distribution condition?
All expected counts are greater than or equal to 5.
Describe the Chi-square distribution.
It is not a normal distribution, it is right skewed, and only allows for positive values.
What are the two parts of a chi-square test for homogeneity?
Overall test to see if there is convincing evidence to support a hypothesis and the follow up analysis to decide which parameters differ and by how much.
What does the chi-square test for association/independence test for?
Weather two categorical variables are associated in one population.
Alternative hypothesis for GOF
At least 1 of the claimed proportions is incorrect.
What calculator function is used to find p-value?
Chi-square cdf (upper, lower, df)
If p-value is less than alpha, do you accept the null, and what is this known as?
T or F- when determining expected counts we assume the null is correct.
True
What three values does both chi-square test for homogeneity and association/independence solve for?
Chi-squared, degrees of freedom, and p-value
Null hypothesis for Chi-square test for homogeneity.
There is no difference in the distribution of proportions.
What is the equation for expected counts?
(row total)*(column total)
Over all total
Chi- square test for Association/Independence is used to study what type of relationship?
The Relationship between two categorical variables across a single population.
Chi-square for homogeneity test allows us to compare what?
The proportions of success in 1 or 2 populations with 2 proportions.
What relationship is studied in chi-square test for Association/independence?
Null hypothesis for Association/Independence
There is no association between the two variables. The two variables are independent.
What is the equation for a chi-square statistic?