All Questions
17 questions
4
votes
2
answers
407
views
Whether the population exists in an experimental study?
In my oral exam one of my teachers asked whether the population exists in an experimental study.
I answered: "Yes. the population exists in an ...
1
vote
0
answers
158
views
How do I write sum of squares and degrees of freedom for multiple Latin squares put together?
I have notes from my professor in which a Latin square model ($s$ treatments in an $s \times s$ square) is described as follows:
\begin{align*}
Y_{ijk} &= \mu + \alpha_i + \beta_j + \gamma_k + \...
- 82.8k
0
votes
1
answer
168
views
Unbiased Estimator for Mean Response to Treatment
$\newcommand{\eps}{\varepsilon}\newcommand{\szdp}[1]{\!\left(#1\right)}$
Problem Statement: Consider the following model for the responses measured in a randomized block design containing $b$ blocks ...
- 4,027
1
vote
0
answers
40
views
Variance of effects in $2^kr$ factorial design
I'm working through The Art of Computer Systems Performance Analysis, a statistics book focused on analyzing computer performance, and I don't follow the logic for computing the variation of effects ...
- 111
25
votes
2
answers
46k
views
How do you "control" for a factor/variable?
To my understanding, "Control" can have two meanings in statistics.
Control group: In an experiment, no treatment is given to the member of the control group.
Ex: Placebo vs Drug: You give drugs to ...
1
vote
1
answer
49
views
How can I test whether an individual treatment mean significant or not?
Suppose by complete randomization design, I reach into a decision that there is at least difference between two treatment means. That is, my hypothesis is
$$H_o:\mu_1=\mu_2=\mu_3=\mu_4=\mu_5$$
$$...
CommunityBot
- 1
0
votes
1
answer
12k
views
Tukey's Test or LSD Fisher
I'm trying to solve the above exercise, but my question begins with which test should I choose: Tukey test or Fisher's LSD?
I read several things and still can not tell the difference between the two ...
3
votes
1
answer
37k
views
What is the difference between "Unweighted", "Weighted" and "Least Squares" Means?
These concepts have always confused me. In terms of DOE, I think the problem arises when the design is "unbalanced". So,
what are their differences?
Why do you choose one over the other/reasons?
In ...
- 64.8k
1
vote
2
answers
2k
views
$2^{5-2}$ Design : Alias Structure
$2^{5-2}$ Design
Design Generators: $D=AB\quad E=AC$
Defining Relation: $I=ABD=ACE=BCDE$
$$\text{Aliases}$$
$$A=BD=CE=ABDE$$
$$B=AD=ABCE=CDE$$
$$C=ABCD=AE=BDE$$
$$D=AB=ACDE=BCE$$
$$E=ABDE=AC=BCD$$...
- 125
2
votes
2
answers
6k
views
Difference between Research Design and Experimental Design
What is the difference between Research Design and Experimental Design?
I can't see any difference. Both of them need to establish Causality.
Both of them are the arrangement for collection and ...
- 82.8k
4
votes
1
answer
314
views
Design of Experiments
Suppose a dermatologist wants to study the effectiveness of two different preparations of a skin lotion using two different forms of application, such as one versus two applications per day. She has $...
CommunityBot
- 1
0
votes
1
answer
2k
views
Tukey test in factorial experiment
Use Tukey's test to determine which levels of the pressure factor are
significantly different for the data.
I already did the anova table
My question is when making comparisons in Tukey test,...
CommunityBot
- 1
1
vote
1
answer
93
views
Do the different levels of treatment in a completely randomized design come from different population?
Suppose in a completely randomized design , a treatment A have four levels. When we check whether the means of four levels are statistically significant ,i.e.,
$$H_0:\mu_1=\mu_2=\mu_3=\mu_4$$
$$\text{...
- 128k
1
vote
1
answer
2k
views
Is Randomized Complete Block Design a two-way anova?
Isn't Randomized Complete Block Design a two-way anova ? Can it be one-way ?
As far i understand, since there is treatment effect and also block effect in RCBD, it is two-way anova.
But can it be ...
- 82.8k
1
vote
0
answers
85
views
Fractional Factorial Design with Highest Resolution
In the book Design and Analysis of Experiments by Douglas C. Montgomery , it is written that
We usually like to employ fractional designs that have the highest ...
CommunityBot
- 1
3
votes
1
answer
760
views
Fractional Factorial Design
In a $2^5$ design, it is believed that only the main effects $(A,B,C,D, E)$ and $AB,AC$ interaction effects are non-zero. I need to construct a fractional factorial with minimum number of runs which ...
- 21.3k
2
votes
1
answer
167
views
Should I use ANOVA to analyse this experiment?
We performed an experiment on bacterial growth whereby optical density was recorded for three flasks of E. coli bacteria every 30 minutes for 4 hours. 2 flasks upon the 2 hour mark were inoculated ...
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