Test #3

Question 1

What is a univariate?

Answer 1

• descriptive, set us up for our other analyses (looks at symmetry, calculates important values), also you can describe a sample with these.

Question 2

What is a bivariate?

Answer 2

• you can begin to answer some questions here, mainly how are my variables related?
• it shows the distribution of one variable across the categories of another variable.

Question 3

What are marginal cells?

Answer 3

• are the row and column totals on the edges of the table.

Question 4

What is a proportion and a percent?

Answer 4

proportion - 0.30
percentage - 30%

Question 5

What is chi-square test?

Answer 5

when we cannot measure the central tendency
- we can, however, take a look at the difference the expected cell counts and the observed cell count.

Question 6

What does the expected cell count equation?

Answer 6

row total x column total/total table

Question 7

what is an observed count?

Answer 7

the frequencies actually observed in the sample data.

Question 8

What is the notation of chi-square?

Answer 8

X2

Question 9

How do we calculate the chi-square?

Answer 9

• write out your null and alternative hypothesis
• calculate your observed and excepted counts for your table
• choose an alpha level (P=0.00/p= 0.01/p=0.05/p=0.1)
• calculate degrees of freedom (number of categories -1)
• get your critical chi-square value from a table
• use the formula to calculate the chi-square value for your table.

Question 10

What is a ho and a ha?

Answer 10

HO - there is no difference between nationality and quality of life following a heart attack.
HA - There is some relationship between nationality and quality of the life following a heart attack.

Question 11

What is the understanding of hypotheses and when do we accept/reject them?

Answer 11

• if the chi-squared value is at or above the chi-square value for your degrees of freedom, then we reject the null hypothesis.
• if we reject the null, we can say that our findings are significant at our chosen alpha level
• if we cannot reject the null hypothesis, then we don’t have a significant relationship.

Question 12

How do we calculate your degrees of freedom when you are doing a chi-square?

Answer 12

• df= (row-1) x (column - 1)
• count the # of rows in the chi-square table and subtract 1.
• count the # of columns and subtract 1.
• multiply the number of step 1 by the number from step 2.

Question 13

What is the alpha (significant levels) values?

Answer 13

• the maximum risk of making a false positive conclusion that you are willing to accept.
• common significant levels are 0.05 and 0.01

Question 14

What does an r-squared value mean?

Answer 14

• the proportion of the variance in the response variable that can be explained by the predictor variable.
• the value can range from 0 to 1.