Hypothesis Testing Flashcards
The statistical assessment of a statement or idea regarding a population
Hypothesis Testing
The hypothesis that the researcher wants to reject, denoted Ho
Null Hypothesis
* The hypothesis that is actually tested and is the basis for the selection of the test statistics.
Two-tailed test for the population mean
Ho = u = uo, Ha = u =/ uo
One-tailed test for the population mean
Ho: u <= uo
Ha: u > uo
Statistic calculated by comparing the point estimate of the population parameter with the hypothesized value of the parameter specified in Ho.
Test Statistic
Test-Statistic Calculation
(Sample Statistic - Hypothesized Value) / SE of sample
2 Types of Errors in Hypothesis Testing
Type 1: The rejection of null hypothesis when it is actually true, alpha == % that Type 1 happens
Type 2: The failure to reject the null hypothesis when it is actually false, 1-alpha == % that Type 2 happens
The probability of obtaining a test statistic that would lead to a rejection of the null hypothesis, assuming the null hypothesis is true,
P-value
If sample, n<30, and the distribution is non-normal, we have no reliable statistical test.
…
T-statistic Calculation
t = (Xbar - uo)/ (s/n^(1/2))
Used with t-statistics for testing the means of two normally distributed populations are equal, when the variances of the population are unknown but assumed to be equal.
pooled variances
Test used for hypothesis testing concerning the variance of a normally distributed population.
Chi-square Test
*Asymmetrical and approaches the normal distribution in shape as the degrees of freedom increases.
Chi-Square Calculation
ChiSquare = (n-1)s^2 / sigma^2
s= sample variance sigma^2 = hypothesized population variance
Test concerned with the equality of the variances of two populations, used when the populations are normally distributed.
F-Test
*Is right skewed
F-Test Calculation
F = s1^2 / s2^2
s1 = Variance of s1 s2 = Variance of s2
