FLOW CHART FOR start APPROPRIATE METHODS OF...
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Abby, Helen, Ph.D., Johns Hopkins School of Hygiene & Public Health, Baltimore, 1985. Only one variable of interest? One-Sample problem? YES NO Underlying distribution normal or can central limit theorem be assumed to hold? YES Inference concerning µ? Underlying distribution is binomial? σ known? YES YES One-Sample normal test One-Sample t test YES NO Inference concerning σ NO Use another underlying distribution or use nonparametric methods NO One-Sample binomial test Go to 4 Go to 1 start FLOW CHART FOR APPROPRIATE METHODS OF STATISTICAL INFERENCE NO One-Sample chi-square test for variances
Transcript of FLOW CHART FOR start APPROPRIATE METHODS OF...
Abby, Helen, Ph.D., Johns Hopkins School of Hygiene & Public Health, Baltimore, 1985.
Only one variable of interest?
One-Sample problem?
YES NO
Underlying distribution normalor can central limit
theorem be assumed to hold?
YES
Inference concerning µ?
Underlying distribution is
binomial?
σ known?
YES
YES
One-Samplenormal test
One-Samplet test
YES NO
Inference concerning σ
NO
Use another underlying distribution or use nonparametric
methods
NO
One-Sample binomial test
Go to 4
Go to 1
startFLOW CHART FOR APPROPRIATE METHODS OF STATISTICAL INFERENCE
NO
One-Sample chi-square test for variances
Abby, Helen, Ph.D., Johns Hopkins School of Hygiene & Public Health, Baltimore, 1985.
Two-Sample problem?
YES NO
NO
Underlying distribution binomial?
Use another underlying distribution or use nonparametric
methods
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Underlying distribution normalor can central limit
theorem be assumed to hold?
Inferences concerning means?
YES
YES
Inferences concerning variances
NO
Go to 3
YES
Are samples independent?
Are all expected values ≥5?
YES
Use McNemar’s
Test
NO
Use Fisher’s exact Test
YES
Use Two-Sample test for binomial
proportions or 2 x 2 contingency table
methods
NO
NO
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FLOW CHART FOR APPROPRIATE METHODS OF STATISTICAL INFERENCE
Two-Sample Ftest to compare
variances
Abby, Helen, Ph.D., Johns Hopkins School of Hygiene & Public Health, Baltimore, 1985.
FLOW CHART FOR APPROPRIATE METHODS OF STATISTICAL INFERENCE
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NO
Categoricaldata?
Use another underlying
distribution or use nonparametric
methods
Underlying distribution normal or can central limit
theorem be assumed to hold?
Inferences concerning means?
YES
YES
Inferences concerning variances
NO YES NO
Use r x c contingency table
methods
One-way Analysis of variance (ANOVA)
Bartlett’s test for homogeneity of
variances
Abby, Helen, Ph.D., Johns Hopkins School of Hygiene & Public Health, Baltimore, 1985.
FLOW CHART FOR APPROPRIATE METHODS OF STATISTICAL INFERENCE
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NOYES
YES
Use Two-Sample t test with unequal
variances
NO
Use Two-Sample t test with equal
variances
Are samples independent?
Are variances of two samples equal?
N.B. Test using F test
Use paired t test
Abby, Helen, Ph.D., Johns Hopkins School of Hygiene & Public Health, Baltimore, 1985.
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Interested in relationships between two variables?
YES NO
NO
One variable continuous & one
categorical?
YES
YES NO
Both variables continuous?
FLOW CHART FOR APPROPRIATE METHODS OF STATISTICAL INFERENCE
More than two variables of
interest
Use multiple regression or more advanced
techniques of multivariate analysisLinear
regression
Both variables categorical
Analysis of variance (ANOVA)
Use contingency
table analysisNumber of ways in which
the categorical variable can be classified
One-way ANOVA Two-way ANOVA Higher dimension ANOVA
One Two More than Two
