Unit 7

Question 1

Conditions for a 1 sample t interval

Answer 1

SRS
Independence
N >= 30 or draw box plot - no extreme skewness or outliers
safe to use t procedures

Question 2

When is a one sample t test used

Answer 2

Test a claim about a population mean

Question 3

Conditions for a one sample t test

Answer 3

SRS
Independence
N >= 30 or draw box plot - no extreme skewness or outliers
safe to use t procedures

Question 4

Formula for test statisitc for a 1 sample t interval

df formula

Answer 4

t = xbar - mew / (s/sqrt(n))
df = n-1

Question 5

How to calc p value in a test for a population mean

Answer 5

If
HA: u > [null value], p-value = P(t >= observed test statistic)
• If HA.: u < [null value], p-value = P(t <= observed test statistic)
• If HA.: u # [null value], p-value = 2×P(t >= |observed test statistic|)

Question 6

Conditions for 2 sample t interval

Answer 6

2 SRS
both indepedent
both n1 and n2 should be > 30

Question 7

What is a calc used for in a 2 sample t interval

Answer 7

T* value