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Unit VI Scholarly Activity

Michell Muldrow

Columbia Southern University

Research Methods

Dr. Senft

November 6, 2021

Data Analysis: Hypothesis Testing

Independent Samples t Test: Hypothesis Testing

Ho4: There is no statistically significant difference in mean scores between prior training and revised training.

Ha4: There is a statistically significant difference in mean scores between prior training and revised training.

t-Test: Two-Sample Assuming Unequal Variances
	Group A Prior Training Scores	Group B Revised Training Scores
Mean	69.79032258	84.77419355
Variance	122.004495	26.96456901
Observations	62	62
Hypothesized Mean Difference	0
df	87
t Stat	-9.666557191
P(T<=t) one-tail	9.69914E-16
t Critical one-tail	1.662557349
P(T<=t) two-tail	1.93983E-15
t Critical two-tail	1.987608282

The data shows a mean value of 69.79 for Group A and 84.77 for Group B. These p-value of 1.93 indicates that there is a significant difference between the training programs. The p-value 1.94 is considerably less than the alpha level of 0.05 which leads to a rejection of the null hypothesis. Therefore, the alternative hypothesis is accepted which states that there is a significant difference between the mean values between Group A and group B.

Dependent Samples (Paired Samples) t Test: Hypothesis Testing

Ho5: There is no statistically significant difference in employee blood lead levels between pre exposure and post exposure.

Ha5: There is a statistically significant difference in employee blood lead levels between pre exposure and post exposure.

t-Test: Paired Two Sample for Means
	Pre-Exposure μg/dL	Post-Exposure μg/dL
Mean	32.85714286	33.28571429
Variance	150.4583333	155.5
Observations	49	49
Pearson Correlation	0.992236043
Hypothesized Mean Difference	0
df	48
t Stat	-1.929802563
P(T<=t) one-tail	0.029776357
t Critical one-tail	1.677224196
P(T<=t) two-tail	0.059552714
t Critical two-tail	2.010634758

The data shows a mean value of 32.86 μg/dL for the Pre-Exposure Group and 33.29 μg/dL for the Post-Exposure Group. The mean values show a p-value of 0.059552714 > .05. Therefore, the null hypothesis is accepted that there is no statistically significant difference in mean values between the pre-exposure and post-exposure in lead blood levels.

ANOVA: Hypothesis Testing

Ho6: There are no statistically significant differences in ROI between air monitoring, soil remediation, water reclamation, and health and safety training.

Ha6: There is a statistically significant differences in ROI between air monitoring, soil remediation, water reclamation, and health and safety training.

Anova: Single Factor
SUMMARY
Groups	Count	Sum	Average	Variance
A = Air	20	178	8.9	9.357895
B = Soil	20	182	9.1	3.042105
C = Water	20	140	7	6.631579
D = Training	20	108	5.4	1.410526
ANOVA
Source of Variation	SS	df	MS	F	P-value	F crit
Between Groups	182.8	3	60.93333333	11.9231	1.76E-06	2.724944
Within Groups	388.4	76	5.110526316
Total	571.2	79

The data provided the average for Air which is 8.9, Soil which is 9.1, Water which is 7, and

Training which is 5.4. The p-value of 1.76 < .05; we would therefore reject the null hypothesis

and the alternate hypothesis will be accepted. There is a statistically significant different mean

values for the between the Air , Soil , Water and Training. In addition, it is not possible to tell

there the differences occur so in order to find that out we would need to conduct a two-piece test.