24. People with an autoimmune disease like lupus produce antibodies that react to their own tissues. Research has shown that lupus-prone strains of mice have B cells with redudd expression levels of the receptor gene SYRIIB, suggesting that low expression of this gene might contribute to the autoimmune reaction. To test this, McGaha et al. (2005) experimentally enhanced expression of the FcyRIIB gene in bone marrow taken from a lupus-prone mouse strain and transplanted it back into irradiated mice of the same strain. Other mice of the same strain were subjected to the same procedures but received bone marrow that was not enhanced for FcyRIIB expression (i.e., the sham treatment). Mice in a third group were left untreated. Auto- immune reactivity was measured six months later. The following is a frequency table indi- cating the highest dilution of blood serum, in a fixed series of dilutions, at which reactivity could be detected (a high dilution reflects a high autoimmune reactivity).
24. People with an autoimmune disease like lupus produce antibodies that react to their own tissues. Research has shown that lupus-prone strains of mice have B cells with redudd expression levels of the receptor gene SYRIIB, suggesting that low expression of this gene might contribute to the autoimmune reaction. To test this, McGaha et al. (2005) experimentally enhanced expression of the FcyRIIB gene in bone marrow taken from a lupus-prone mouse strain and transplanted it back into irradiated mice of the same strain. Other mice of the same strain were subjected to the same procedures but received bone marrow that was not enhanced for FcyRIIB expression (i.e., the sham treatment). Mice in a third group were left untreated. Auto- immune reactivity was measured six months later. The following is a frequency table indi- cating the highest dilution of blood serum, in a fixed series of dilutions, at which reactivity could be detected (a high dilution reflects a high autoimmune reactivity).
MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
Related questions
Question

Transcribed Image Text:b. What distinct purposes do the sham-
treated and untreated groups serve in this
experiment?
c. Calculate the mean and standard deviation of
dilution measurements in each group.
d. We would like to test whether the mean
dilutions of the three groups are different.
Based on your answers to parts (a) and (c),
why should we be cautious about employing
ANOVA?
e. Choose a transformation that overcomes
the main difficulty in part (d). Display your
resulting sample means and standard
deviations.
f. Using the transformed data, test whether
there is a difference among treatment groups
in the mean of dilution measurements.
g. What method would we use next to help
decide which group means differed from the
others?

Transcribed Image Text:24. People with an autoimmune disease like lupus
produce antibodies that react to their own
tissues. Research has shown that lupus-prone
strains of mice have B cells with redudd
expression levels of the receptor gene SYRIIB,
suggesting that low expression of this gene
might contribute to the autoimmune reaction. To
test this, McGaha et al. (2005) experimentally
enhanced expression of the FcyRIIB gene in
bone marrow taken from a lupus-prone mouse
strain and transplanted it back into irradiated
mice of the same strain. Other mice of the same
strain were subjected to the same procedures but
received bone marrow that was not enhanced for
FcyRIIB expression (i.e., the sham treatment).
Mice in a third group were left untreated. Auto-
immune reactivity was measured six months
later. The following is a frequency table indi-
cating the highest dilution of blood serum, in
a fixed series of dilutions, at which reactivity
could be detected (a high dilution reflects a high
autoimmune reactivity).
Dilution
measured
100
200
400
800
Total
Number of mice
Sham-
Enhanced treated
0
34209
SNEOO
0
3
2
5
Untreated
a. Is this a balanced design? Explain.
55246
0
0
Expert Solution

This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 2 steps with 2 images

Recommended textbooks for you

MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc

Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning

MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc

Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning

Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON

The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman

Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman