Study Guides (248,551)
United States (123,414)
Statistics (13)
STAT 301 (11)
Midterm

# Mean difference between independent samples, sampling distribution, hypothesis testing, test statistics and p-values

4 Pages
64 Views

Department
Statistics
Course
STAT 301
Professor
Brett Hunter
Semester
Fall

Description
17 October Mean difference between independent samples Goal is to compare the mean of the variable for one population to the mean of the variable in the second So our parameter of interest is μ – μ1 2 We can have two samples of different sizes, n and n .1 2 Assumption Both n a1d n are2greater than or equal to 30 (or both populations normal/combo) Sample 1 and Sample 2 selected independently of each other Sampling Distribution We want to make inferences about μ – μ 1 2 Take 2 independent samples Find x 1 , the point estimate for μ 1 Find x 2 , the point estimate for μ 2 x 1 - x2 is the point estimate for μ - μ 1 2 We need the sampling distribution of x 1 - x2 in order to construct hypothesis tests and confidence intervals If the random samples are independent of one another and n and n are b1th larg2 (≥ 2 2 x x σ1 σ2 30), then 1 - 2 ~ N(μ –1μ , 2 n + n ) 1 2 Hypothesis Testing Most common hypotheses compare the difference to 0, but could also compare to some other number. Hypotheses Upper tail (is μ 1arger than μ ?)2 H0: μ1≤ μ 2 HA: μ1> μ 2 OR H : μ – μ ≤ 0 0 1 2 HA: μ1- μ 2 0 Lower tail (is μ 1maller than μ ?) 2 H0: μ1≥ μ 2 HA: μ1< μ 2 OR H0: μ1– μ ≥20 HA: μ1– μ <20 Two tail (are μ 1nd μ dif2erent?) H0: μ1= μ 2
More Less

Related notes for STAT 301
Me

OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Join to view

OR

By registering, I agree to the Terms and Privacy Policies
Just a few more details

So we can recommend you notes for your school.