Exam 3 Flashcards
(46 cards)
What does it mean to test for differences?
difference testing or analysis is used to see where there are differences between or among groups of people or texts
What does it mean that groups are significantly different on a measure or variable?
this means that the differentiations noted in the results of the data had a cause and did not occur by chance
What does the null hypothesis say about differences?
in order for there to be a statistically significant difference, the statistical difference has to be less than 0.05 (p =< 0.05)
Type of Nominal question
select which assessment practice you prefer for providing feedback (written, digital, or audio)?
Type of Ordinal question
rank order your favorite to least favorite method for providing feedback (written, digital, audio)
Type of Interval question
On a scale of 1-5, how likely are you to write out your feedback by hand?
Type of Ratio question
For how many assignments, do you provide typed out feedback?
What test is used for nominal questions?
chi-square test
What test is used for ordinal questions?
median test
What test is used for interval questions?
t-test and analysis of variance (ANOVA)
What test is used for ration questions?
t-test and analysis of variance (ANOVA)
What are 3 Requirements for Statistical Significance?
significance level, degrees of freedom, and critical value
What does significance level mean?
the probability for rejecting the null hypothesis which can be equal to or less than 0.05 (p =< 0.05)
What does degrees of freedom mean?
the number of scores that are free to vary?
How is the degree of freedom calculated?
it varies depending on the type of test
What does critical value mean?
the number your test results must meet or beat for them to be considered significant
How is the critical value calculated?
use the degrees of freedom # and significance level to look it up using Harris (1998) chart
Example of 1-tailed RQ/hypothesis that would require use of difference testing
Is there a difference in levels of confidence providing students with feedback between teachers with 2 years of teaching experience and teachers with 5 years of teaching experience? I predict that teachers with 5 years of experience will have more confidence in providing feedback than teachers with 2 years of experience.
Example of 2-tailed RQ/hypothesis that would require use of difference testing
Is there a difference in levels of confidence providing students with feedback between teachers with 2 years of teaching experience and teachers with 5 years of teaching experience? I predict that there will be differences between the levels of confidence amongst teachers with 5 years of experience and 1 year of experience.
In the following question, which is the IV (grouping value) and which is the DV (variable measured):
Is there a difference in levels of confidence providing students with feedback between teachers with 2 years of teaching experience and teachers with 5 years of teaching experience?
The IV is 2 groups: teachers with 5 years of experience and teachers with 2 years of experience.
The DV is levels of confidence.
For what type of data can a Chi-square be used for?
nominal
What is the difference between a single sample Chi-Square test and a multiple sample Chi-Square test?
The one-variable chi-square test is used when there is 1 IV or 1 DV being tested.
The two-variable chi-square test is used when there are 2 variables being tested such as 2 IVs or 1 IV and 1DV.
What are the 4 steps for a one-variable chi-square test
*List the observed frequency (O) for each category
*List the expected frequency (E) for each category (to calculate this, divide the # of observations by the total # of categories
*For each category:
-subtract the expected from the observed (O-E).
-Square the difference.
-Divide the difference with the expected frequency (E)
*Add up the results for each category to get the chi-square value
How is the degree of freedom calculated in a chi-square?
subtract 1 from the number of categories (n-1)