The non-independent tag has no wiki summary.
0
votes
0answers
25 views
ANOVA with semi non-independent data
Nectar accumulation in plants is induced by Wounding, and also modulated by the amount of Light reaching a plant. We were asking if nectar response to those factors were localized (in the same branch ...
1
vote
1answer
59 views
Non-independence of IVs in a random forest model
How is a random forest model affected if some of the variables are not independent?
6
votes
3answers
210 views
regression with non-independent data
I will be performing regression on subjects total scores from 2 player games (prisoners dilemma) that they will be playing. I am aware that including both players score from a game will cause problems ...
0
votes
1answer
160 views
How to deal with correlated fixed effects in a mixed-effects model?
I am trying to predict (binary) memory for pictures based on two continuous fixed effects: memorability and clutter. Using a mixed effects model, I found that both effects predict memory and including ...
2
votes
0answers
207 views
How to compare the means of two dependent groups when the groups are not paired?
I have performed a behavioral experiment on bees from one single hive. I let them fly under two different conditions and now I want to compare the average flight speed in the two conditions. The ...
1
vote
0answers
68 views
Order statistic of dependent chi-squares
I was wondering if someone could please help me with the following. I am trying to find the pdf of a set of dependent $\chi^2$ random variables. Suppose $x_1,x_2,...,x_n$ are independent normals $x_i ...
2
votes
0answers
45 views
Dealing with dependant data when estimating probability of an event happening
I have 10 year worth of data from 1970 to 1980 (40 quarters).
For each quarter I have five measurements M1, M2, M3, M4 and M5.
TWIST: Although the data I have is on individual patient level the ...
3
votes
0answers
72 views
Using taxonomic levels as factors in random forests: does it make sense? Is it needed?
I want to test the effect of a set of predictors (ecological and morphological factors) on a categorical response variable (an animal behaviour).
As far as I've read, random forests do not make ...
1
vote
0answers
103 views
Logistic Regression with dependent observations
I have a dataset that contains 100 different patients over 5 year’s period. Every patient is examined each month with regard to particular illness and marked as healthy or ill (0 or 1). Every person ...
0
votes
1answer
37 views
Is computer network throughput an independent variable?
The central limit theorem assumes independent variables and I want to apply it to study the performances of my network speed (computer networks). What I have a is the throughput measurements of my ...
3
votes
1answer
177 views
Experimentially proving that random variables are independent
I just had a very simple (possibly very dumb) question.
How would I, experimentally prove that two random variables drawn either from the same population or two different populations are independent ...
1
vote
1answer
55 views
1
vote
1answer
142 views
How to calculate probability for n dependent events
I have a dataset containing some approx. 11 million instances, all of which can be labelled as either class A or class B. I know a priori that approx. 1,000 of these instances belong to class A, and ...
0
votes
1answer
54 views
Test data for randomness with repetitions
I have an experiment where I am trying to determine whether the answering behavior of participants can be explained as random answering. I.e. every participants will have to answer multiple questions ...
3
votes
1answer
125 views
Overall type I error with dependent tests
Imagine we test 2 dependent samples: For example, we first test an overall sample (treatment vs. control) and then a subset of this overall sample (treatment sbg vs. control sbg). In this case, we are ...
4
votes
0answers
49 views
Comparing performance after CV over a single dataset : does it violate the independence assumption?
Cross validation lets us get multiple estimates of the generalization performance of an algorithm when the performance cannot be estimated for each example independently. (As with an F1-score, we ...
12
votes
2answers
475 views
How do I test a nonlinear association?
For plot 1, I can test the association between x and y by doing a simple correlation.
For plot 2, where the relationship is nonlinear yet there is a clear relation between x and y, how can I test ...
1
vote
0answers
26 views
Constructing a model from multiple non-independent and unreliable predictors?
I have an interesting modelling problem in which I am trying to forecast the occurrence of a type of weather event using an empirical model driven by measurements of a number of different physical ...
1
vote
2answers
320 views
Statistical test to compare multiple treatments on the same 'individual' over time
I'm looking for a statistical test or tests to compare the effects of different 'treatments' on a single 'individual' over time. The single 'individual' could be one person or a group acting as a ...
1
vote
0answers
37 views
How can I estimate a “rank” dependent variable in a multivariate dataset?
I have a dataset where $x_{1}$, $x_{2}$, ..., $x_{k}$ are of mixed type and $y$ is a ranking from $1$ to $n$ where $n$ is the number of observations in the dataset. I'd like to predict $y$ based on ...
3
votes
1answer
180 views
Estimation the standard error of correlated (binomial) variables
Say we have N voters from some group (N binomial variables). Each voter has a preference on voting about some issue (probability of "success" p), which depends on the preferences of other voters.
...
3
votes
3answers
251 views
Optimal estimation of a mean from non-independent data
I have the following model:
$Y_1=\beta+\varepsilon_1+\varepsilon_2$
$Y_2=\beta+\varepsilon_3+\varepsilon_4$
$Y_3=\beta+\varepsilon_1+\varepsilon_4+\varepsilon_5$
...
3
votes
1answer
105 views
What hypothesis test should I use to test for equal “success” probabilities in paired binary data?
I have the following data set:
70 participants, who answered arithmetic questions of different length.
A wrong answer coded as 0, a correct answer coded as 1.
I want to know if there is a ...
2
votes
1answer
116 views
Computing confidence intervals for non-independent data
I am using the survey package in R to t-test data that not independent (it is a time series) by creating a survey object and ...
1
vote
1answer
356 views
What is the difference between linearly dependent and linearly correlated?
Please explain what is the difference between if two variables are linearly dependent or linearly correlated.
I looked up the wikipedia article but didn't get a proper example. Please explain it ...
1
vote
2answers
220 views
Calculating probability of project tasks, and most likely ending date?
Say I have a project (you know the typical one you can represent using a Gantt Chart )
If I where to assign a particula probability to each of the tasks in the Gantt... say for example:
Task1 (2 ...
0
votes
1answer
92 views
Standard error of binomial variables derived from continuous variables
I'm currently working on a project measuring willingness to pay (WTP) for a particular product. The data we are collecting are continuous variables denominated in the local currency. One thing we ...
-1
votes
1answer
91 views
High-dimensional dependent binary explanatory variable
I am dealing with a data set containing roughly $n=4000$ binary observations $Y_1, \ldots, Y_n$ with $p=1000$ binary explanatory variables. I suspect that a lot of these explanatory variables are not ...
0
votes
0answers
67 views
Cross Validation using NON-independent Data
i got a problem with cross-validation!
I got two studies, t(N=1200) and t+1(N=200) respectively. The 200 corporations form t+1 are also part of the t0-Data. In t+1, there are two significant ...
1
vote
0answers
50 views
Good reference on analysis of dependent samples
Is there a good reference (book if exists) about mathematical statistics of dependent random variables? Something along the lines of Casella and Berger's textbook, but for dependent samples.
I'm not ...
0
votes
1answer
673 views
How to add two dependent random variables?
I know, I can't use convolution.
I have two random variables A and B and they're dependent.
I need Distributive function of A+B
0
votes
1answer
169 views
How can I calculate a confidence interval for the mean based on non-independent data?
In Chemical industrial, samples are often analyzed multiple times, e.g. 5 samples and each was analyzed 2 times with 10 data points in total. What would be the confidence interval for the mean ...
5
votes
0answers
133 views
Variance of the Kaplan-Meier estimate for dependent observations
Can someone help me find a way to estimate the variance of the Kaplan-Meier estimate with dependent observations? Specifically, I have failure time data from patients with several different ...
3
votes
0answers
120 views
Testing for the existence of dependencies in time series
What methods exist to test for the existence of any sort of dependence in a time series? This is in contrast to something like auto-correlation, which tests for a particular type of dependency. Is ...
1
vote
1answer
735 views
How to calculate a confidence Interval for a mean of subjects from two sessions?
How to calculate confidence interval for this mix of independent(different subjects) and dependent (data of same subject from two sessions) observations?
There are 12 subjects and the mean is ...
0
votes
0answers
283 views
How to calculate overall error from a series of dependent experiments?
Salmon were collected and induced to spawn. The percent of the fish collected who spawned successfully was 63%, so P(S)=0.63. A sample of the eggs were then fertilized and the percent of eggs that ...
2
votes
1answer
198 views
How to model change over four time points on an ordinal variable where some participants have missing data at some time points?
Context
I am accumulating a data set that is starting to look like this:
I have about fifty individual animals (n=50) that I am studying over, say, a year
Every three months or so, I would measure ...
2
votes
2answers
52 views
Do non-significant correlates of a DV, which is significant, suggest anything about the effect of that DV?
Let's assume one has an analysis in which there are multiple correlated DVs (average correlation .46) being examined in separate univariate analyses (e.g. t-tests; insufficient df and frustration ...
3
votes
2answers
133 views
Best way to compare software usage data over time across independent conditions?
I created a software platform on which about 110 participants could contribute at any time of their choosing over the course of 12 weeks (think something like a wiki). These participants were then ...
4
votes
2answers
985 views
How to model the sum of Bernoulli random variables for dependent data?
I have almost the same questions like this:
How can I efficiently model the sum of Bernoulli random variables?
But the setting is quite different:
$S=\sum_{i=1,N}{X_i}$, $P(X_{i}=1)=p_i$, $N$~20, ...
4
votes
2answers
444 views
Generating dependent time series from a given distribution?
How can I generate dependent time series from a given marginal distribution? I want to be able to adjust the level of dependence, to influence the predictability of the series, which will be given as ...
1
vote
0answers
249 views
Do two variables need to be independent in order to obtain a correlation?
I would like to find the correlation between two variables. It was suggested to me that two variables should be independent; otherwise it is not meaningful statistically to calculate a correlation. ...
2
votes
1answer
233 views
Is it possible to correct for violating the assumption of independence for nonparametric tests?
Is it possible to correct for violating the assumption of independence for nonparametric tests?
I have a categorical independent variable and a categorical and binary dependent variable, and each ...
3
votes
1answer
163 views
Modelling dependence between random variables
Is there any comprehensive reference on (or introduction to) how people have tried to model non-independent random variables? I already know about mixing processes, which express in various ways ...
1
vote
0answers
214 views
Confidence interval for ratio in timeseries
I have a time series X(t). Each X(t) has three possible outcomes : A,B,C. I am interested in the ratio of A,B,C to the total. Assuming N is the total number of data points I have gathered for X(t),
...
6
votes
1answer
243 views
Survival analysis, one cohort, two classifications
I'm wondering about this question:
short version:
how to adequately compare the effect of a reclassification of the same subjects on survival
long version:
I have one cancer cohort that was sorted ...
8
votes
6answers
670 views
How problematic is it to control for non-independent covariates in an observational (i.e., non-randomized) study?
Miller and Chapman (2001) argue that it is absolutely inappropriate to control for non-independent covariates that are related to both the independent and dependent variables in an observational ...
7
votes
3answers
681 views
Recommendations - or best practices - for analyzing non-independent data. Specific example relating to pain perception data provided
I am seeking recommendations and/or best practices for analyzing non-independent data. In particular, I am curious about non-independent data that does not reflect typical repeated-measures time-based ...
