All Questions
16 questions
1
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81
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Experiment design - response variable is a sum over a period, low power
I would like to run a statistically rigorous experiment, similar to that of an E-commerce A/B test.
I want to create a checkerboard of time periods where I alternate between treatments A and B. ...
- 11
1
vote
2
answers
983
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What statistical test is appropriate for a pretest/posttest experimental/control group study?
I thought this would be a relatively straightforward question, but I'm having difficulty finding a decisive answer. Let's say I'm planning to run a study to test the effectiveness of a new type of ...
1
vote
1
answer
75
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Between-subject design and within-subject anlyses
I have a between-subject design in which there are two groups (A, B) and two conditions (x, y). I ran an ANOVA and found no interaction whatsoever and no significant differences in the two conditions.
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- 67
0
votes
0
answers
93
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1 experimental group - 6 control groups: ANOVA or t-tests or something else?
Objective: I want to find out, if a certain machine learning algorithm can select the right 100 stocks out of my stock universe of 2.000 stocks, such that they achieve better combined yearly returns ...
- 1
1
vote
1
answer
956
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How to use Design of Experiment (DoE) to reduce the number of simulations?
I am planning to do simulation for parametric study and there are 9 parameters in total. I was suggested to use DoE to reduce the number of simulations that I need to do. I studied the basic of DoE ...
- 13
0
votes
2
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49
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Confused how to test my ranked data
I am conducting an olfactory preference experiment. Basically, I have a tube with vanilla scent on one end and chocolate scent on the other. I put flies into the tube and after 10 minutes marks the ...
0
votes
1
answer
74
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Comparing means of samples from different populations
I have two equally long time series samples, drawn from two different populations, I would like to test if the means of the two samples are statistically different given population size differences, ...
- 290
1
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1
answer
274
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2X2 ANOVA: low power, statistical significance for only 1 IV, medium-low effect size
BACKGROUND:
I run a 2X2 Between-Subjects ANOVA. I obtained:
a low power (< 0.30) for both Independent Variables
a not statistically significant result for one of the Independent Variables.
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2
votes
1
answer
2k
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Biological experiment - statistical significance of 6 treatments vs control - ANOVA?
I am working on a biological problem and I am struggling to run a meaningful statistical analysis of my samples.
I have treated a number of cells with six different concentrations, and I would like ...
- 121
0
votes
1
answer
50
views
Fundamental question about applying Anova
I have a fundamental question about applying ANOVA.
Suppose we are testing 4 drugs which reduce blood pressure. Our experiment contains 4 drugs + 1 Placebo. We give these to 3 types of patients (...
- 3
0
votes
0
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99
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number of questionnaires and sample size
Is there any correlation between number of questionnaires used in a study and the sample size in order to obtain accurate measurement?
- 657
0
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1
answer
185
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Two-way ANOVA doesn't detect differences between conditions in a specific group?
OK, so let's say we have independent variables Condition (A or B) and Race (1 or 2 or 3). Then say we have a dependent variable X. We can run a two-way ANOVA to find out if there's an effect due to ...
- 323
1
vote
1
answer
93
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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{...
- 1,617
5
votes
2
answers
11k
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When to create a control group with paired T test
So if I wanted to measure the effect of a drug on a group of people, I think I would use a paired T test based on my research. But what if something caused a change in my group that I did not account ...
- 53
1
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0
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22
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Conditions on ratio of $\frac{\sigma_{BIB}^2}{\sigma_{RB}^2}$
I'm attempting to solve a question about the variances of random block design versus balanced incomplete block design. I feel I am close to having an answer, but I'm not quite there yet.
Question:
...
- 133
2
votes
2
answers
554
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What is the most appropriate test for a multi-year different group/yr experiment?
I've been working on a research project for close to five years now. For my thesis I have to show how "well" did my approach improve things.
Setup: Every year we use a tool A to brainstorm and ...
- 14.9k