Chi-Square Test

Question 1

Descriptive vs. Inferential Statistics

Answer 1

Descriptive statistics describe the population

Inferential Statistics draw conclusions about the population by comparing and contrasting

Question 2

What are some examples of descriptive statistics?

Answer 2

Mean, median, mode, standard deviation, etc.

Question 3

What are some examples of inferential statistics?

Answer 3

T-test, chi-square, etc.

Question 4

What is the tool we use to decide when to use what statistical test?

Answer 4

The decision tree

Question 5

What are the 2 forms of inferential statistics?

Answer 5

Parametric and Nonparametric Data

Question 6

Desribe Parametric Data

Answer 6

This type of data has to ratio or interval.
Parametric statistics we can typically assume that the data has come from a normal distribution which allows us to make inferences about the parameters of the distribution.
This form of data does have specific units for the data, such as lbs, cm, etc.

Question 7

Parametric statistics are used for _____ or _____ level data.

Answer 7

Ratio or Interval

Question 8

Describe Nonparametric Data

Answer 8

This type of data has to ordinal or nominal.
Nonparametric data is not required to fit a normal distribution because the data is not continuous.
This form of data does not have any specific units for the data, such as pain scale, gender, etc.

Question 9

Nonparametric statistics are used for _____ or _____ level data.

Answer 9

Ordinal or Nominal

Question 10

Is a Chi-Square test parametric or nonparametric?

Answer 10

Nonparametric

Question 11

What is the purpose of a Chi-Square test?

Answer 11

To compare 2 or more sets of nominal data that have been arranged into categories by frequency counts.
Used to determine whether there is a significant difference between the expected frequencies and the observed frequencies.

Question 12

Describe the significance of a contingency table for a Chi-square test

Answer 12

Chi-square test can be used to test for independence between rows and columns of a contingency table.

Question 13

How do you calculate the degress of freedom from a chi-square table?

Answer 13

df = (rows-1) (columns-1)
For example: A table with 2 rows and 2 columns have a degrees of freedom of 1
(2-1) (2-1) = 1

Question 14

How do you calculate the expected frequency from a chi-square table?

Answer 14

= (sum of the rows)(sum of the columns) / N

Question 15

Are bbserved and expected frequencies one-tailed or two-tailed tests?

Answer 15

One-Tailed

Question 16

Frequencies represent _______ , not ranks or percentage.

Answer 16

individual counts

Question 17

Categories in a chi-square test are _____ and ____. What does this mean?

Answer 17

exhaustive
mutually exclusive
It means that means all subjects are divided into each category.

Question 18

Are overlaps allowed in a chi-square test?

Answer 18

NO

Question 19

What is the level of significance (p value) for a chi-sqaure test?

Answer 19

0.05

Question 20

How do you find the calculated value for a chi-square test?

Answer 20

= X(squared) = sum of (O-E) squared / E

Question 21

How do you find the critical value for a chi-sqaure test?

Answer 21

found in chi-square table (appendix)

Question 22

In order to reject: calculated value ___ table value

Answer 22

great than (>)

Question 23

So if the calculated value is less than the critical value what can we conclude?

Answer 23

The null hypothesis is s not rejected, and we would can conclude that our observed data is similar to the expected data.
In other words the group frequencies are not significantly different.

Question 24

In order to reject: p value ___ table (set) value

Answer 24

Less than (<)