Inferential Statistics in Decision-making
ramswork
FinalReviewLesson1.pptxInferential Statistics
Final Review Session
Review for final
Can you read, write, and analyze statistics?
2
Pop Quiz: What test would you select…
Examining differences between pre-post scores of the same students.
Examining similarities between student’s math & science scores.
Analyzing if there is a relationship between males and females passing/failing driving tests.
Determining if there is a difference between 5 schools monthly # of discipline infractions.
Examining if there is a similarity between elementary and middle school students ranked incentives for test performance.
After an ANOVA reveals a significant difference in groups.
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Pop Quiz: Answers
Examining differences between pre-post scores of the same students.
Examining similarities between student’s math & science scores.
Analyzing if there is a relationship between males and females passing/failing driving tests.
Determining if there is a difference between 5 schools monthly # of discipline infractions.
Examining if there is a similarity between elementary and middle school students ranked incentives for test performance.
After an ANOVA reveals a significant difference in groups.
Paired Sample t-test
The students would be matched in each row, and scores reported in columns.
Regression test
The students would be matched in each row, and the scores placed in the columns.
Chi-Square Test
Male/female and pass/fail observations in a 2X2.
ANOVA
Each school would be a separate column, and the number of infractions placed in the rows.
Spearman’s r s
In one column place the rank for the incentives for elementary, and in the second column place the ranks for incentives for middle school.
Independent Sample t-test
Run separate t-tests for each combination.
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If each test was significant (p<.05)…
Examining differences between pre-post scores of the same students.
Examining similarities between student’s math & science scores.
Analyzing if there is a relationship between males and females passing/failing driving tests.
Determining if there is a difference between 5 schools monthly # of discipline infractions.
Examining if there is a similarity between elementary and middle school students ranked incentives for test performance.
After an ANOVA reveals a significant difference in groups.
Paired Sample t-test
There was a significant difference between student’s pre-post test results. Look at the means…
Regression test
There was a significant relationship between student’s math and science scores.
Chi-Square Test
Gender is related to passing or failing driving tests. Look at which gender passed at a higher rate.
ANOVA
There is a significant difference between number of discipline infractions at the different schools. Run a post-hoc test to determine diff.
Spearman’s r s
There is a similarity between incentive preference. Age did not affect preference.
Independent Sample t-test
There was a significant difference between group A and group B.
Wait! What do the results really mean?
5
Review basic concepts:
What is the difference between descriptive and inferential statistics?
Calculate and define: Mean, Median, Mode, Range
Define and describe distributions: normal, bimodal
Parametric vs. nonparametric testing
Quantitative research vs. qualitative research
Research questions and hypothesis testing
Research questions guide our decisions and determine our statistical tests (see last week’s lesson for a deeper discussion)
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Inferential Statistics
When p < .05…
When p > .05…
Identify when to use, calculate, report (according to handbook), and interpret:
Spearman’s rs
Chi-Square
Paired Samples t-test
Independent Samples t-test
ANOVA (and post-hoc testing)
Regression/Pearson Product Moment r
Correlations and cause/effect relationships
< means we reject the null hypothesis, assume results more extreme occur fewer than 5 times in 100
Means we do not reject the null, we can’t rule out random chance
Spearman’s rs-ranked data, correlations
Chi-square- observed data, counts
Paired sample-logically paired data, pre/post opposite of Pearson/regression
Independent- differences in data
ANOVA- differences in 3 or more, indep. T-test for post hoc, Tukey’s HSD, or other appropriate test
Regression or Pearson
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Final Thoughts…
Thank you for your participation and effort in this class.
Final is due by midnight (EST).
