Sample Proportions and Chi Square
The sampling distribution is approximately normal if__________ and __________.
Sample observations are independent and the CLT success-failure condition is met
The equation needed to find the sampling error for the confidence interval of a sample proportion is _________.
SE = square root [(pxq)/n]
An ANOVA is typically used when you need to_______
Test the means of 3 or more sets of data (though an ANOVA can be used for two data sets, generally a t-test is used for this)
Correctly fill in the blank: Correlation _________ causation
Correlation does not necessarily mean causation.
R2 is known as the ___________
correlation coefficient
A confidence interval for a proportion is set up as ____________.
The sample proportion +/- z(SE) where z(SE) is the margin of error
For the t-distribution, normality occurs when _________ and _________.
The observations are independent and the sample size is large (n is greater than or equal to 30)
The null hypothesis for an ANOVA test is __________
Ho: u1 = u2 = u3 = .....
The means of all data sets are equal, and there are no differences.
The x variable is the independent (or explanatory) variable. The y variable is the dependent (or response) variable.
R takes on values between _____ and _____.
-1 and 1
The null and alternative hypotheses for a Chi square test are ___________.
Ho: Expected proportions are true
Ha: At least one proportion is not true or differs from what we expected.
For the t-distribution, as the degrees of freedom gets ________, the curve more closely resembles normality
The alternative hypothesis for an ANOVA is __________
Ha: At least one mean differs
The means of all data sets are NOT equal.
An estimate of a scatterplot is known as the _________.
line of best fit
The closer the correlation coefficient gets to |1|, the ________ the correlation.
stronger
We reject the null hypothesis of a Chi-square test when __________
The X2 value is greater than the critical value (X20.5)
For a two-tailed t-distribution, the null and alternative hypotheses are ___________.
Ho: u1 - u2 = 0
Ha: u1 - u2 does not equal 0
When making a conclusion about an ANOVA, the _______ should be used.
p-value
An outlier can be identified on a scatterplot as it is _________.
outside the norm and will influence the line of best fit
R = 0 can be described as ___________.
no correlation
The degrees of freedom for a Chi square test is found by __________
df = k-1 where k is the number of categories
The t-score is found using the formula__________
t = (sample mean - population mean)/SE
The the p-value is lower than 0.5, ____________
the null hypothesis is rejected.
Correlation where one variable increases as the other decreases is known as __________.
negative correlation
R = 0.8 can be described as ________
highly positive correlation