Melanoma Treatment ONE Way ANOVA Analysis
Assignment #3 ONE Way ANOVAMelanoma treatment: An experiment evaluated the use of genetically engineered white
blood cells in the treatment of patients with melanoma. Patients were divided into three
cohorts. Patient cohort 1 received genetically engineered lymphocytes that were cultured
ex vivo for 19 days. Cohort 2 received cells that were cultured for between 6 and 9 days.
Cohort 3 received cells that were generated by a second rapid expansion performing after
8 to 9 days. Cell doubling times were as follows.
Cohort 1 (N=3) 8.7 11.9
Cohort 2 (N=11) 1.4 1.0
Cohort 3 (N=4) 0.9 3.3
1.3 1.0 1.3 2.0 0.6
0.8 0.7 0.9 1.9
Either create a file with these data or download the file MORGAN2006* from the
companion website. Most statistical programs require you to enter that data into two
columns: one column for the explanatory variable (COHORT) and the other for the
response variable (DOUBLING). Your final data table should have 2 columns and 18
1. Create this as an xls file in excel and attach for your assignment. (10 points)
2. Then upload to BrightStat for analysis. (10 points for correct upload and for
using the correct test)
(BrightStat, Version 1.3.1)
3 Run the descriptive statistics and report mean, sample size, SD, skewness and
Kurtosis. Provide the output. (10 points for the output, 5 for each types of statistical
point mentioned above (25 points) (15points for analysis of the information.)
Provide your complete analysis and assumptions for the relevance that was
determined from descriptive statistics. This should be written in a scholarly format
with appropriate citation and reference to the literature to support underlying
4. Run a one-way ANOVA with post-hoc analysis and interpret results. (55 points)
a. provide the output data. (10 points)
b. Define the term heteroscedasticity. What does this mean, how is it determined?
Heteroscedasticity means the variance of the errors is not constant across observations or
unequal scatter of residual points
c. Conduct Leven’s test for unequal variance. What does this result reveal? (20
H0: The variances of the samples are equal.
Ha: The variances of the samples are unequal.
p-value= 0.034> 0.05, do not reject null hypothesis
Conclusion: there is sufficient evidence that the variances of the samples are equal
d. Interpret the f ratio, significance and post hoc analysis. Cite resources to
reinforce concepts here to analyze and critique the results of testing. (20 points)