chi square

Question 1

In χ^2
tests for count data, all else being equal, the greater the value of the test statistic the
smaller the p-value

Answer 1

True. The p-value is the area to the right of the test statistic.

Question 2

The χ^2 distribution tends toward the standard normal distribution as the degrees of freedom
increase.

Answer 2

False. As the degrees of freedom increase, the χ^2 distribution gets closer to a normal distribution, that part is true.
But the mean of a χ^2 distribution is equal to its degrees of freedom (not
0, as for the standard normal distribution).

Question 3

The χ^2 distribution is skewed to the right.

Answer 3

true, but skewness sec as dog inc

Question 4

In χ^2 tests for count data, we lose 1 degree of freedom for each parameter we estimate using
our data.

Answer 4

true

Question 5

χ^2 statistics can take on negative values.

Answer 5

false X^2 test statistic is the sum of squared terms

Question 6

The χ^2

test statistic has exactly a χ^2 distribution

Answer 6

False, it is only an approximation

Question 7

The mean of a χ^2 distribution is equal to its degrees of freedom

Answer 7

true

Question 8

For a given set of expected counts in a two-way table of a given size, the greater the difference
between the observed and expected counts, the greater the value of the χ
2
test statistic

Answer 8

true

Question 9

For a given set of expected counts in a two-way table of a given size, the greater the difference
between the observed and expected counts, the smaller the p-value.

Answer 9

true

Question 10

For a given set of expected counts in a two-way table of a given size, the greater the difference between the observed and expected counts, the greater the evidence against the null hypothesis.

Answer 10

true

Question 11

For a 2 × 2 table, the value of the χ^2 test statistic is the square of the corresponding Z test
statistic

Answer 11

true