Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [pooling]

Pooling, eg for variance, is used when several groups or populations are assumed to have a common property (a common parameter value) and the information from all the groups or populations are used together to estimate that common property.

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What is global max pooling layer and what is its advantage over maxpooling layer?

Can somebody explain what is a global max pooling layer and why and when do we use it for training a neural network. Do they have any advantage over ordinary max pooling layer?
Eka
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Combining probabilities/information from different sources

Lets say I have three independent sources and each of them make predictions for the weather tomorrow. The first one says that the probability of rain tomorrow is 0, then the second one says that the probability is 1, and finally the last one says…
Biela Diela
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How to calculate pooled variance of two or more groups given known group variances, means, and sample sizes?

Say there are $m+n$ elements split into two groups ($m$ and $n$). The variance of the first group is $\sigma_m^2$ and the variance of the second group is $\sigma^2_n$. The elements themselves are assumed to be unknown but I know the means $\mu_m$…
user1809989
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Why is max pooling necessary in convolutional neural networks?

Most common convolutional neural networks contains pooling layers to reduce the dimensions of output features. Why couldn't I achieve the same thing by simply increase the stride of the convolutional layer? What makes the pooling layer necessary?
user3667089
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Such thing as a weighted correlation?

I have some interesting data on the most popular musical artists streamed divided by location into about 200 congressional districts. I want to see if it's possible to poll a person on his or her musical preferences and determine whether he or she…
Chris Wilson
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What does pooled variance "actually" mean?

I am a noob in statistics, so could you guys please help me out here. My question is the following: What does pooled variance actually mean? When I look for a formula for pooled variance in the internet, I find a lot of literature using the…
Hanciong
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How to get pooled p-values on tests done in multiple imputed datasets?

Using Amelia in R, I obtained multiple imputed datasets. After that, I performed a repeated measures test in SPSS. Now, I want to pool test results. I know that I can use Rubin's rules (implemented through any multiple imputation package in R) to…
wisc88
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Errors-in-variables regression: is it valid to pool data from three sites?

I recently had a client come to me to do a bootstrap analysis because an FDA reviewer said that their errors-in-variables regression was invalid because when pooling data from sites the analysis include pooling data from three sites where two sites…
Michael R. Chernick
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Panel Data: Pooled OLS vs. RE vs. FE Effects

We had some discussion about the usefullness of Pooled-OLS and RE Estimators compared to FE. So as far as I can tell, the Pooled OLS estimation is simply an OLS technique run on Panel data. Therefore all indivudually specific effects are completely…
Kosta S.
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Pooling calibration plots after multiple imputation

I would like advice on pooling the calibration plots/statistics after multiple imputation. In the setting of developing statistical models in order to predict a future event (e.g. using data from hospital records to predict post hospital discharge…
IWS
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How does Max Pooling handle Odd Image Dimensions?

For the even image dimension case, max pooling is simple to understand - it simply performs convolution over the image with the max operator with a $x$-by-$x$ kernel with a stride of $x$. However for the case of images with odd image dimensions, you…
AGentleRose
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Confusion about pooling layer, is it trainable or not?

I have read in many places such as Stanford's Convolutional neural networks course notes at CS231n (and also here, and here and here), that pooling layer does not have any trainable parameters! And yet today I was informed by someone that in some…
Hossein
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Applying Rubin's rule for combining multiply imputed datasets

I am hoping to pool the results of a pretty basic set of analysis performed on a multiply imputed data (e.g. multiple regression, ANOVA). Multiple imputation and the analyses have been completed in SPSS but SPSS does not provide pooled results for a…
user81715
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Distribution of the pooled variance in paired samples

Suppose a bivariate normal populations with means $\mu_1$ and $\mu_2$ and equal variance $\sigma^2$ but having a correlation of $\rho$. Taking a paired sample, it is possible to compute the pooled variance. If $S^2_1$ and $S^2_2$ are the sample…
Denis Cousineau
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How to pool results from post hoc lsmeans analysis across multiple imputations with MICE

I have five imputed datasets created with MICE in R, and am running run some post hoc analyses using the lsmeans package. Although MICE has great functions to easily pool and compare models (e.g. pool() and pool.compare()), they won't work…
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