Question

Will medal and fan! Please help!
A two-way table of counts is analyzed to examine the hypothesis that the row and column classifications are independent. There are three rows and four columns. How many degrees of freedom does the chi-squared distribution have?
Choose one answer.
A. 5
B. 6
C. 7
D. 12
E. n-1

Answer 1

@Destinymasha

Answer 2

@thomaster

Answer 3

@ParthKohli

Answer 4

@ganeshie8

Answer 5

for a nxm table, df= [n-1]*[m-1]

Answer 6

so 2x3=6

Answer 7

How about this one?
On the Titanic, people have theorized that the female passengers were saved while the male passengers perished. Here is the data with the passengers categorized by their gender and whether they survived or not.
Gender Died Survived Totals
Female 126 317 (443)
Male 680 168 (848)
Totals (806) (485) (1291)

a. Fill in the totals in the table above. ( the ones in parentheses are the ones that were blank)

b. Fill in the table below with the expected counts. Let your calculator figure out the expected counts (decimals are ok).
Gender Died Survived Totals
Female
Male
Totals
c. Run a complete test to determine if the variables of survival and gender are independent or not. Be sure to provide a clear conclusion.

Answer 8

for the test I got these values
chi^2=332.205
p=3.180224e-74
df=1

Answer 9

Can you help @P0sitr0n ?

Answer 10

df is right

Answer 11

@amistre64

Answer 12

tell me your steps ....

Answer 13

What do you mean?

Answer 14

well, the parts pretty much guide you along the process ... they give you the observed, and they want you to fill in a table for the expecteds. how would you determine the expected values?

Answer 15

I don't remember and I can't find where it was taught in my textbook.

Answer 16

IF this was a truely independant setup then we would observe that:

\[P(A_1|B_1)=P(X_1|D)\] does that make sense?