Data, events, processes, etc, are non-independent if knowledge of 1 provides some information about the state or value of the other.

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2
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1answer
35 views

What is the long run variance?

How is long run variance in the realm of time series analysis defined? I understand it is utilized in the case there is a correlation structure in the data. So our stochastic process would not be a ...
4
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0answers
18 views

how to test equality of proportions at different times

Here is my question. 20 (worm) mothers produce males + females and hermafrodites (many every hour). I want to test if the proportion of males + females born on day #1 is the same as in days #2 and ...
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8 views

Co-variance matrix and Factor graph representation

I have problem in fundamental understanding of factor graph representation: I am trying understand the relation between the Co-variance matrix and associated factor graph, of a Normally distributed ...
0
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0answers
7 views

Average-to-average comparison with non normal response variable and dependent explanatory variable

I would like to compare the average expression of a gene in three different brain regions of a mammal (see the table below). Unfortunately, I had only 11 mammals to calculate each average. Moreover ...
0
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0answers
4 views

How do I account for non-independence in occupancy modeling?

I have conducted a survey to look at why badgers are visiting some gardens but not others. I have data on badger presence / absence and garden features that might influence badger presence in that ...
3
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0answers
40 views

Logistic Regression Model with Non-Independent Regressors

I'm looking to create a model that takes into account multiple logistic variables in an ordered process. To illustrate, what I'm trying to do is similar to the following: ...
2
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1answer
26 views

Dependent or Independent samples? I cant decide! Help

I'm confused i have assignment where i have to determine if the samples are dependent or independent. The sample is of 100 people, where their reaction times from their dominate and non-dominate hands ...
0
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1answer
34 views

Are two variables that are dependent also correlated? / Can two dependent variables not be correlated? [duplicate]

I cannot find the answer to my question anywhere, I hope someone can help. I did a Chi-Square test with several variables to see if they were dependent or independent. The result showed that they ...
0
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0answers
13 views

Proving dependence of two variables

I am working on the Technology Acceptance Model (TAM). As can be seen, U and E determine A. A and U determine BI, and BI determines the Actual System Use. Based on the constructs given in the ...
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0answers
20 views

Population version of Kendall's Tau Equation

I am reading about concordance and Kendall's Tau. I understand both concepts from an intuitive level. The empirical formula for Kendall's tau is given by: $$ t = \frac{c-d}{c+d} $$, where c is the ...
0
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1answer
19 views

Analyzing multiple, within-subjects, non-independent ordinal rankings

So I'm working with some previously collected data where participants (N=139) were asked to rank 3 types of events (1 being best, 3 being worst) for 6 separate scenarios. The question of interest is ...
4
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0answers
78 views

Empirical distribution function of overlapping time series data

If we model asset return volatility for periods of more than one (say more than one day) there is the square-root rule which holds true under some assumptions. On the other hand practitioners ...
2
votes
1answer
38 views

Continuous joint entropy with fully dependent variable

Consider a variable $X$ with a continuous uniform distribution in the interval $[a,b]$ and a variable $Y$ that is fully dependent on $X$, i.e., $p(Y=y\ |\ X=x) = \delta (x-y)$, where $\delta$ is a ...
2
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1answer
201 views

PDF of dependent variables

In my recent question an answer was given, and I am able to compute it myself. Still, I'd like to understand where does that answer come from. Hence, what's the approach to handle dependent variables ...
12
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1answer
354 views

Why do mixed effects models resolve dependency?

Say we're interested in how student exam grades are affected by the number of hours that those students study. To explore this relationship, we could run the following linear regression: $$ ...
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0answers
11 views

Multivariate distributions, k-margin's, Bayesian Networks, and dependency

Suppose that we have a multivariate probability distribution with four variables, X, Y, Z, and W. Let us assume that the joint distribution can be factored as follows: $$ f_{X,Y,Z,W}(x,y,z,w) = ...
1
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1answer
65 views

What is the demonstration of the variance of the difference of two dependent variables?

I know that the variance of the difference of two independent variables is the sum of variances, and I can prove it. I want to know where the covariance goes in the other case.
0
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2answers
45 views

Is the the dependence of the residual of a ARMA time series model only based on AR term?

Lets suppose we fit two time series models AR(1) and ARMA(1,1) to a data series. Should be the results of the ljung-Box test for the residuals be the same for these models? I mean does MA term affect ...
1
vote
1answer
19 views

Independent observations, and might this require a repeated measures ANOVA?

below is a text for an assignment i am working on. I am getting really confused thinking about wether the the observations are independent in this example, because all of the people work together and ...
2
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1answer
37 views

Chi-squared distribution and dependence

We know that for a group of independent random variables $\{X_i\}_{i=1}^n$ s.t each $X_i$ is distributed as a chi-squared distribution with degree of freedom one ($\chi_1^2$), the sum of these random ...
7
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2answers
113 views

Approaches for generating synthetic survey data with dependent answers?

I would like to produce synthetic survey data. At the moment I produce independent answers between questions according to an arbitrary discrete distribution as in this question. I want to generate ...
0
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0answers
31 views

Chi square test of independence with multivariate nominal data

I used a list-type open-ended question to collect responses, in which respondents can list up to 6 items. After coding the items, I have the multivariate nominal data. I want to check if my IV ...
2
votes
0answers
31 views

Cumulative distribution function of dependent variables

I have measured packet delays on several different radio channels $c_1, c_2, c_3$ and got three streams of delay data: $d_{11}, d_{12}, d_{13}, \dots$ $d_{21}, d_{22}, d_{23}, \dots$ $d_{31}, ...
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0answers
44 views

How to use difference in mean team weight to predict winner of college football game

I think I need a new statistic. I am trying to make the case that the average weight difference between college football teams is related to won-loss record. I am studying the Big 10 and Big 12 ...
1
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1answer
38 views

How to correlate count variables that are nested / non-independent?

Above is a snapshot of a subset of a larger dataset, N=61. Group is the group number, Iterations is indicating the ...
8
votes
1answer
127 views

Plain language meaning of “dependent” and “independent” tests in the multiple comparisons literature?

In both the family-wise error rate (FWER) and false discovery rate (FDR) literature, particular methods of controlling FWER or FDR are said to be appropriate to dependent or independent tests. For ...
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0answers
12 views

Mantel Test? correlation between two variables measured at four sites over four sessions

I am looking for a way of testing and measuring the correlation between two variables (Var1 and Var2) collected at four sites through four sessions (each one at the same time). Thus, due mainly to ...
2
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0answers
58 views

Hypothesis testing with non-iid observations

I have a dataset with observations which violate the independent and identically distributed (iid) assumption. The dataset is composed by a number of post-click conversion events (purchases on a ...
3
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1answer
45 views

How to test paired observations

I have a set of data that look like this: ...
1
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1answer
35 views

Analysis of clustered data

I have records of $multiple$ visits from many different patients in several different clinics (i.e. visits nested within patients nested within clinic) and plan to perform an analysis that takes into ...
2
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0answers
31 views

Comparing two correlated dependent variables

I have two dependent variables that I want to predict. One is a normally-distributed continuous variable, and the other is a binary categorical variable (0 or 1). They're moderately correlated so that ...
5
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1answer
81 views

Asymmetric measure of non-linear dependence/correlation?

I am definitely not a statistician/mathematician so feel free to tell me I'm an idiot if I am. As far as I can tell from my Wikipediaing all of the main measures of dependence are symmetric and ...
1
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1answer
26 views

Differences between reviewers and people being reviewed in terms of learning achievement

An experiment about the review process was made. Participants were students visiting a course. One group had to solve some exercises and the other group had to review their work and give feedback. At ...
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0answers
13 views

Non idependence within groups

I have to train a machine learning model for classifying two groups. Unfortunately, my positive group has a small number and many cases are not independent from each other (observations taken in ...
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111 views

Best machine learning methtod for classificating datasets with non-independent cases within the groups

I have to perform binary classification of my data with supervised machine learning, but I have some difficulties working with my data set. It consists many genetic mutations that have parameters ...
2
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1answer
52 views

Example of dependence with zero covariance

This is a constructivist question. Please provide a bi-variate distribution or density/mass function of two absolutely continuous/discrete (but not mixed-type) random variables, which (may) have ...
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0answers
23 views

Flow of influence in a v-structure for Probabilistic Graphical Models

I'm not very sure I understand why an observed v-structure have different flow of influence behaviour for a directed and an undirected graph. What is the intuition behind the actual definition for ...
2
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0answers
63 views

ANOVA of pairwise (non-independent) data in R

I am trying to do a one-way ANOVA of data that is generated from pairwise comparisons, and am having difficulty resolving the problem of non-independence. I have 12 populations, and for each pairwise ...
2
votes
1answer
192 views

Why is independence required for two- sample proportions z test?

I read in several books as well as in different posts (e.g. here) that independence is required for two-sample proportions z tests. But so far I could not find an explanation why this is the case and ...
3
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2answers
142 views

How does one find the mean of a sum of dependent variables?

I know that the mean of the sum of independent variables is the sum of the means of each independent variable. Does this apply to dependent variables as well? Thanks.
0
votes
1answer
38 views

Resources to understand why dependence is a problem [duplicate]

For many statistical procedures, it seems the observations must be independent. For example the observations within each group in a two-sample t-test must be independent for the standard error/P-value ...
0
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0answers
15 views

Method to analyze data which has no repetitional measurement

I am trying to find a good method to analyze my data, and I am really lost. My data is only from one riverstretch, no repetitional measurement. I look at three stretches of the river, near ...
5
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1answer
38 views

multi stage binomial “process”

I wish to model the retransmission time of a file that divided into K blocks. I know the successful blocks of first transmission obey the binomial distribution $$ X_1 \sim \text B(K,p) $$ , p is the ...
0
votes
0answers
24 views

Logistic regression and cluster ID

The dataset consists of all prescriptions classified as on or off-label (0 or 1), meaning possible more than one prescription per child (pnr-number) I want to know the off-label rates per year for ...
0
votes
2answers
62 views

how to deal with dependence/interaction among covariates in a cox regression model

In case of a linear regression, if we are to account for interaction between two regressors x1 and x2, we write a model like ...
0
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0answers
25 views

How can I make use of correlations between datasets for building multiple models?

I'm building models for a bunch of spatial points. Linear regressions models, for now, but I will have expand to more complex ones (non-linear, time-series models, etc.). So far, I've looked at the ...
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0answers
15 views

Is analysis of variance here a correct test?

Suppose I have measurements: $f(x_i, y_i)$ $f(v_i, w_i)$ $f(x_i, v_i)$ $f(y_i, w_i)$ If I put these into groups $(xy), (vw)$ and $(xv, yw)$ and do a single-factor ANOVA with the previous three ...
0
votes
1answer
33 views

Are identical samples independent?

Are results of two different tests performed on exact same sample independent or dependent? For example, if the same group of rats were injected some drug A, results collected, then long enough time ...
1
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2answers
97 views

Compare differences in dependent frequencies

I would like to compare two error rates (proportion of incorrect answers in questions with dichotomous response-format) for two different items, and I am looking for some advice on how to do that. ...
1
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1answer
80 views

Assume (x,y) are drawn from independent & identical distribution when y=f(x)

Sometimes we say the following: $X$ is some training data given by $X:=\{(x_1,y_1),...,(x_l,y_l)\}\subset R^d \text{x}R$. Assume that the training data had been drawn from independent and identical ...