All Questions
Tagged with pearson-r regression
68
questions
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44
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Yes or no: is Pearson’s r is a measure of goodness of fit to an affine function? [duplicate]
Is the statement "Pearson’s r is a measure of goodness of fit to an affine function" literally true? Why or why not?
- 171
1
vote
1
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26
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Testing for correlation
I'm new to statistics. I'm solving a problem where I'm given three sets of data, the measured sizes of the population of rabbits, the drug dose that's been given to each of them and the method of ...
- 193
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33
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Selection of covariates for partial correlation?
Are there any recommendations on procedures to identify relevant variables for a partial correlation between $r(X, Y)$?
To me, it appears most reasonable to only include those $Z_1, Z_2,\ldots,Z_n$ as ...
- 415
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2
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75
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What is this equation for?
$$t = \frac{r}{\sqrt{\frac{1-r^2}{n-2}}} \sim t_{n - 2}$$
with $$r = \frac{S_{xy}}{\sqrt{SC_{xx} SC_{yy}}}$$
I've just found this equation with no direct data to of what can I get from it, I couldn't ...
- 270
7
votes
2
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582
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What is the 'right' slope formula of a regression? deltas or Pearson?
this may be a silly question, but still:
I've been told that the slope formula equals the rise/run ratio, like this:
$$
m = \frac{rise}{run} = \frac{y_2 - y_1}{x_2 - x_1}
$$
in which rise equals ...
- 781
3
votes
2
answers
833
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If Pearson's correlation is zero does this imply no linear correlation?
I am looking to detect linearity in a dataset. Linearity as in the linearity assumption of linear regression. (There exists a linear relationship between the independent variable, x, and the dependent ...
- 131
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280
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Positive Pearson but negative Spearman and Kendall
I tried all 3 correlation tests, and got the following results:
Pearson's test: 0.04132983
Spearman's test: -0.009821993
Kendall's test: -0.02230622
I don't understand how the values can be so vastly ...
- 61
3
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1
answer
174
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Strange definition of coefficient of determination
In Wei and Kusiak, 2015 a metric is used to evaluate the performance of a time-series prediction model. The paper calls it
[the] correlation coefficient ($R^{2}$)
and defines it as
$R^{2} = 1-\frac{...
- 135
6
votes
1
answer
448
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Why normalize the vectors to calculate the Pearson correlation coefficient?
I learned from this answer that the correlation $R$ is $\cos(\theta)$ and $\theta$ is the angle between a dependent vector $Y$ and an independent vector $X$, but I learned from this article that the ...
- 6,810
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27
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Proving non-correlation with very disperse distributions
I'm fairly new to statistics and came up with a problem.
I have a sample with a variation coefficient CV = 0.517 for variable x, and I want to prove this variable is not correlated with a second ...
- 235
1
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87
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Adjusted R2 Validity for Big amounts of observations
I am working with a dataset that has a big amount of observations (2000). The purpose of my work is to find which dependent variables (x1, x2, x3...) are linked to my independent variable (y). I have ...
- 13
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0
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65
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Is the correlation coefficient more than a measure of the tightness of fit? [duplicate]
or in other words, to what extent and under what conditions, the correlation coefficient can be indicative of what a regression slope signifies (in the case of a linear bivariate model)?
0
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13
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Total inconsistence between Pearson correlation in a correlation matrix vs Pearson test AND Rsquare smaller than Pearson [duplicate]
I have a very urgent issue that I need to solve this weekend.
If I create a linear model between 2 variables and look for the R square with this code:
...
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1
answer
391
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How to test if two independent variables correlations are statistically different?
I have two independent variables (A and B), and one dependant variable (Y). I can calculate all the correlations (A-B, A-Y, B-Y...).
I see a difference between the Pearson correlations A-Y and B-Y (e....
- 3
6
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1
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7k
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Simple linear regression: R2 not equal to squared Pearson coefficient
The R2 of a simple linear regression model is the squared Pearson
correlation coefficient (r) between the observations and the fitted
values.
Isn't the above in contradiction with the fact that the ...
- 6,187