Linked Questions
20 questions linked to/from What is covariance in plain language?
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what exactly does correlation mean [duplicate]
what exactly is a correlation of zero meant to be, does that mean that changes in x does not affect y, if that is the case, from the scatter plot
That is completely false, as sometimes as x increases,...
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Pearson Correlation Question [duplicate]
I am a beginner on calculating correlations and I would like to ask possibly a very simple question.
If I have two variables that I want to perform correlation on, and those variable are of unequal ...
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How would you explain covariance to someone who understands only the mean?
...assuming that I'm able to augment their knowledge about variance in an intuitive fashion ( Understanding "variance" intuitively ) or by saying: It's the average distance of the data ...
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How would you explain the difference between correlation and covariance?
Following up on this question, How would you explain covariance to someone who understands only the mean?, which addresses the issue of explaining covariance to a lay person, brought up a similar ...
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What is compound symmetry in plain english?
I recently realized that a mixed-model with only subject as a random factor and the other factors as fixed factors is equivalent to an ANOVA when setting the correlational structure of the mixed model ...
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Can somebody illustrate how there can be dependence and zero covariance?
Can somebody illustrate, as Greg does, but in more detail, how random variables can be dependent, but have zero covariance? Greg, a poster here, gives an example using a circle here.
Can somebody ...
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Does covariance equal to zero implies independence for binary random variables?
If $X$ and $Y$ are two random variables that can only take two possible states, how can I show that $Cov(X,Y) = 0$ implies independence? This kind of goes against what I learned back in the day that $...
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How to understand the correlation coefficient formula?
Can anyone help me understand the Pearson correlation formula?
the sample $r$ = the mean of the products of the standard scores of variables $X$ and $Y$.
I kind of understand why they need to ...
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Basis of Pearson correlation coefficient
Pearson correlation coefficient is calculated using the formula $r = \frac{cov(X,Y)}{\sqrt{var(X)} \sqrt{var(Y)}}$. How does this formula contain the information that the two variates $X$ and $Y$ are ...
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Physical meaning of correlation?
Assume that X depicts a random variable denoting the time it takes someone to sweep the floor today and Y be the time it takes him tomorrow and Z be the time it takes him on the last day of October.
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user8968
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Correlation between numerical and categorical data in R [duplicate]
I have a dataset with over 20 variables. Some of them are numerical and some of them are categorical:
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How to calculate error of percentage ratio?
I have the following problem:
I am counting a subset of cells from a tissue in Drosophila (fruit fly) at different days after "birth". At Day0 I obtain a population of flies, and dissect some of these ...
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Why would we ever use Covariance over Correlation and Variance over Standard Deviation?
I am unable to understand the practical use of Covariance and Variance.
In my understanding, Covariance and Correlation are both measures of how one variable changes with respect to another. The only ...
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What does this scatterplot mean? Uniform distributions? [closed]
I am very new to statistics and prob theory:
I am looking at a scatter plot of two random variables, both uniformly distributed on $(0,1)$. The plot is approximatively a straight line, and the book ...
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What does it mean for two variables to be uncorrelated? How is it possible for two variables to be strongly related but still uncorrelated [duplicate]
What does it mean for two variables to be uncorrelated? How is it possible for two variables to be strongly related but still uncorrelated
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