0
votes
0answers
2 views

CNN and kernel sizes: is upsampling useful?

I am playing with Deep Recurrent Q-Network in Reinforcement learning. The architecture I am currently using is similar to the one presented in "Human-level control through deep reinforcement learning"...
0
votes
0answers
11 views

Need help in understand the histograms?

Below graphs are birthrate, deathrate, population and population_growth of all the countries in the world. I don't know how to clearly understand these plots. I don't know what are xaxis and y axis ...
0
votes
0answers
4 views

How can use UDF function in outside of function

I have created UDF Function in R and I want to apply that function in Outside the function, please help me is it possible to do it ?. please explain me to give some example. Thanks Dev
0
votes
0answers
4 views

Faster RCNN - Pyramid of Filters vs Pyramid of Anchors (Reference Boxes)

I'm reading faster RCNN paper now and trying to understand what is the difference between Pyramid of Filters and Pyramid of Anchors methods from the scale point of view. I mean if I use only one ...
0
votes
1answer
9 views

Gradient in batch-size

When we set a batch-size, after each sample of batch passed we take the gradient but wait until last sample of batch to passed and then propagate the sum of gradient of them through the network? Am I ...
0
votes
0answers
9 views

reporting beta coefficient for chunk tests in logistic regression

I have used lrm in the RMS package to construct a logistic regression model with several interaction terms for a recent paper. As part of my strategy, I decided to use Wald Chi-squares on factors ...
0
votes
0answers
12 views

How to forecast a time series in R with ts()

For June 2009 - June 2018, I have prices for product to be delivered that month if bought on the date on the left most column. This below is an excerpt to show the format. The 1-5 and so on r between ...
0
votes
1answer
11 views

Using probit regression coefficients to derive probabilities?

I'm reading a paper here that uses a Probit Regression. I'm not entirely familiar with how this works. But, I'm wondering if there's a way to use the coefficients from Table 3 to derive the ...
0
votes
1answer
11 views

What is the difference between Silhouette Index vs Dunn Index vs Davies-Bouldin Index

I would like to know whether there is any condition that using one cluster evaluation methods (Dunn, Silhouette, Davies-Bouldin) is better than others. I didn't find anything online or inside books, ...
2
votes
0answers
24 views

Calculating the 1 Sample Kolmogorov Smirnov Test Statistic for Normality

Can anyone give me some insight into where this calculation for the KS test statistic is going wrong (see figure 1)? I ran the test in SPSS and SAS as a check. I have used the same process for other ...
2
votes
0answers
15 views

Reliability engineering design values from tests AS/NZS1170

To get design values (the strength of something, for example) designing to Australian/ New Zealand loading code you do $n$ tests and estimate the coefficient of variation of your parent population, $...
1
vote
3answers
52 views

non parametric alternative to simple t-test

I will try to write my problem as accurate as possible, sorry if I forgot to say something. I have 5 numeric variables of 2 populations (each of them with 60 individuals) and for each of those 5 ...
2
votes
0answers
13 views

KL divergence between which distributions could be infinity

I know that KL divergence measures difference between two probability distributions. My doubt is for which of the distributions it could become Infinity, putting it in another way, ...
0
votes
0answers
11 views

How to simulate data for generalized estimating equations (GEE) with logistic link function?

I am working with a pre/post test structure, measuring dichotomous outcomes. I am using GEE to estimate the coefficient for time (also a binary variable, 0 representing pre and 1 representing post), ...
1
vote
1answer
25 views

How to fit a line to data using weighted least squares (WLS) regression?

I am newbie to WLS regression topic. I am being asked to fit a line to a data using WLS. I am working in minitab. My data is as follows: cost (independent variable) (x-axis); production (dependent ...
1
vote
0answers
6 views

Using granger causality test with dummy variable

I have a question whether Granger causality test can be performed if one of the variables is a dummy. I have two variables one continuous variable and then a dummy for an event that is 1 during the ...
1
vote
1answer
9 views

Change in SD when you add funds in a portfolio of VC funds

I would like to measure by how much the standard deviation decrease when I add funds in a VC fund portfolio. Lets supose I have the returns obtained by 400 VC funds. With that information I can ...
2
votes
0answers
12 views

divergence of beta estimates between OLS and regression with ARIMA error

I have physiological time-series data: ~60k observations per channel, ~100 Hz sampling. I will model individual channels with ~20 regressors. Under OLS, given temporal autocorrelation in the data, ...
0
votes
0answers
8 views

PCA - projection matrix terminology

At the end of the PCA algorithm one gets a matrix $U$ (Dxd) such that $z=U^Tx$ (x - D dim.; z - d dim.), $d\leq D$. In multiple sources on the Web I found that $U$ or $U^T$ is named "projection matrix"...
3
votes
2answers
65 views

formal definition of the qqline used in a qqplot

I'm doing some distribution fitting work and I'm looking at Q-Q plots and how they can be used visually to interpret goodness of fit. My data is heavy-tailed so I am looking at Weibull, log-normal, ...
0
votes
0answers
16 views

Which unsupervised machine learning algorithm should I use?

I am observing emails in our online shopping website email address. Some of the emails are spam because they contain hyperlinks, contain information which are not related to our products and some ...
0
votes
0answers
8 views

Log analysis; identify unique messages

I am venturing into area of log file analysis and trying to make sense of thousands of log files generated during regression testing. The log files have messages from a global set. Each log file is ...
0
votes
0answers
10 views

Study design: small sample sizes with high biased attrition rate during the study duration

I am looking to design an experimental framework for assessing the impact of specific marketing interventions (in this case, consumer participation in an event) on downstream consumer behavior (e.g. ...
0
votes
0answers
19 views

What is the probability of Stock B having a return less than 6%? [on hold]

What is the probability of Stock B having a return less than 6%? Facts: 15% average return for the holding period, standard deviation of 9%.
0
votes
0answers
6 views

Assigning Error Bars On Extreme Measures

Extreme measures require principled quantification of the error bars on such measures because of sample size limits. A statement like "90% of scores will fall between X and Y." is of a different ...
0
votes
1answer
13 views

For multiclass classification purpose I have to use a imbalanced dataset

I am facing a problem. It's a multiclass classification problem I have 5 categories A has 107 instances B has 101 instances C has 882 instances, D has 229 instances and E has 129 instances. I used Knn,...
0
votes
0answers
12 views

Propagation of error from y into x

I have a question about error propagation. The figure below shows HDD as a function of temperature. I have determined a minimum in HDD (approximately 1 at approximately 11 degrees) with corresponding ...
0
votes
1answer
17 views

How to interpret and determine the reference levels of independent variables in a regression problem?

I encountered several regression problems in the field of engineering that are formulated similar to the following form (I will ommit the error terms): $$ y=a_0+a_1(x_1-c_{ref})+a_2\ln(x_2/d_{ref})\,,...
0
votes
0answers
12 views

How to create a binary threshold from Cosine distance between 1-D arrays?

I have a graph of the Cosine distance between the question and the sentence most similar to it when there is an answer and when there is none. I want to establish a threshold on the abscissa axis ...
0
votes
0answers
9 views

covariance of longitudinal measures under random intercept/slope model

I am considering a model where I have repeated/longitudinal measures over a number of timepoints from baseline (probably evenly spaced - perhaps with 2 groups) and I assume a random intercepts and ...
0
votes
0answers
6 views

Running analyses with uneven group sizes

I was trying to run a study with 100 people per condition for 4 conditions. When I looked at the results, the group sizes were skewed - some had 80, some had 120. If I'm planning on running a series ...
0
votes
0answers
13 views

Merge two datasets with different units of measurement

I have two physiological data sets coming from two different populations entering the same experiment which includes two IV; Drug vs Placebo (2 level; between-subj) Stimulus type (3 levels; within ...
0
votes
0answers
13 views

Intuitive explanation of the Wald Chi-Squared Test

I am having trouble understanding what the Wald Chi Squared test is used for intuitively. SPSS uses the Wald Test (type III) in the "Tests of Model Effects" box when I run my GEE models, but I don't ...
0
votes
1answer
19 views

Random Forests and Information gain

Suppose you are building random forest model, which split a node on the attribute, that has highest information gain. In the below image, select the attribute which has the highest information gain? ...
-1
votes
1answer
12 views

How to weight features when doing text mining?

I have a case where I'm doing text mining over a list of product titles. In particular I want to run a clustering algorithm. But I also have some information about those products that I think can add ...
0
votes
0answers
14 views

Wind (speed) - a non-iid random variable?

Over a time period of 1 year, half hourly wind speed data is collected. Is it false to state that the collected data is not-iid? I know that wind is seen as a non-stationary process, but does it also ...
1
vote
0answers
8 views

In multivariable quantile regression, how can we determine which observation corresponds with a particular quantile?

I'm trying to use quantile regression to solve an areal interpolation problem as described in this paper: https://www.tandfonline.com/doi/abs/10.1080/00045608.2011.627054 Basically I have a set of ...
-1
votes
1answer
16 views

Classification accuracy on multi classes

My target has 5 classes. My testing dataset has an accuracy of about 34%. Can I assume this is a reasonable model purely based on classification accuracy, since random guessing is 20%.
2
votes
1answer
101 views

Improving spam classification with tensorflow logistic regression

I would like to classify a mail (spam = 1/ham = 0), using logistic regression. My implementation is similar to this implementation and using tensorflow. A mail is represented as a bag-of-words ...
1
vote
1answer
17 views

From OLS to semi-parametric GAM: parametric vs no-parametric

I am quite new to this kind of topic, but for my master thesis i built an multiple linear regression with OLS. Now I want to control for non-linear relationships using a semi-parametric GAM. My ...
0
votes
0answers
17 views

How to use the T-test for the performance of survival time prediction?

I used 2 methods to predict the Survival time of patients. I used the Concordance index (C-index) to evaluate the performance of prediction. I wanted to test if the prediction performance for the ...
2
votes
3answers
91 views

Can PMF have value greater than 1?

Can a Probability Mass Function can have value greater than 1 like we have in Continuous functions(pdf) and why? Please give 1 example if the answer is yes. And If the answer is no then why PDF can ...
2
votes
0answers
6 views

Analyzing behavioral change: Comparing 2 measured weight curves to a model curve

I'm currently in the process of analyzing experimental data and would like to hear your opinion on the method I would like to use to test my hypothesis. I had an experimental setup where I recorded ...
2
votes
0answers
20 views

Similarity between Train and Test data sets

I have multiclass classification dataset and I am using Deep nets for the classification task. To explain the problem, let's assume that I have 5 classes to classify. No matter what I try, be it ...
0
votes
0answers
14 views

Dependent variables with values on a (likert-type) scale

we'd like to conduct a study about the perceived valuation between two persons (let's say A and B that have different characteristics). Therefore, for our dependent variable, we'd like to ask ...
0
votes
1answer
25 views

Cox model with a predictor variable within only one stratum

I'm investigating survival in a cancer patients cohort. The Cox model I'm using is stratified by stage and adjusted for several variables. I would like to add one variable RT (Radiotherapy) which is ...
1
vote
0answers
18 views

How to uniquely identify each Employee in an Organisation with a hash value between 0 and 511 [on hold]

let I be a set of random input values, with I = N . Then h meets this quality criterion if (∀1 ≤ i ≤ n)(|h(I) ∩ Pi| ≈ N/n ) if N >> n. Suppose you want to use Employee numbers to calculate a hash, ...
0
votes
0answers
35 views

Algorithms for everyone [on hold]

Something I've allways wanted to see is a concise run-through of different machine learning algorithms, all on one page: With their pros and cons, what situations they work in best and when they don'...
1
vote
0answers
9 views

Shows negative value in reliability test

How to test reliability in nominal data? MY dependent and independent variables are both in ordinal data. I have to find out the contribution of independent variables in dependent variables. is it ...
1
vote
1answer
9 views

Why convoloution neural net have to find filter values ?

I'm new to ML stuff and one of the thing that I don't understand about CNN, is that why CNN have to find the values of filter at convolution layer, why don' they use existing filters and only find the ...

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