Chapter 9- Intro to the t-statistic

Question 0

What is the equation of the estimated standard error?

Answer 0

SM= √s2/n

Question 1

Define

Estimated standard error(Sm)

Answer 1

An estimate of the real standard error σΜ when the value is unknown

Question 2

Define:

T-statistic

Answer 2

A test used to test hypotheses about an unknown population mean μ when the value of σ is unknown

Question 3

What is the equation for a t-score?

Answer 3

t= χ-μ/Sm

Question 4

What are the steps to calculate a t-score?

Answer 4

1. Calculate the sample mean
2. Calculate the SS
3. Calculate S2
4. Calculate the Sm
5. Calculate t-score
6. Then look it up

Question 5

List the equations you must use.

Answer 5

SS= Σx2-(Σx)2/n
S2= SS/n-1
Sm= √S2/n
t= χ-μ/Sm

Question 6

Define:

Degrees of freedom

Answer 6

The number of scores in a sample that are independent and free to vary. df= n-1

Question 7

Draw the a graph showing the difference between a normal distribution an a t-distribution of 20 and 5

Answer 7

Good

Question 8

What is the difference between a t-distribution and a normal distribution?

Answer 8

The t-distribution is flatter and more spread out. The larger the distribution the closer it is to the normal distribution.