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How do you apply random forest classification, not regression? Keep getting error even though my response variable has been converted to a factor [closed]

I keep getting the error message " Warning messages: 1: In train.default(x, y, weights = w, ...) : You are trying to do regression and your outcome only has two possible values Are you trying to ...
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52 views

Why is the lower bound of the confidence interval of a model's error relatively constant compared to the upper bound? [closed]

I am interested in studying the effect of increasing data samples for a regression model on train error and test error. For this I have used 95% confidence intervals for different values of a sample ...
1k views

Boosting using other "weak learners" than trees

Descriptions of boosting (and specific techniques like gradient boosting) typically talk about "weak learners" in general, and then immediately switch to discussing boosted trees specifically. Why is ...
16 views

Linear mixed models natural splines plotting regression

Eventually I want to use joint modeling. For this, I need to fit a linear mixed model on the biomarker trajectory, with a random slope and intercept for study ID. I want to use natural splines with ...
29 views

Clustering Standard Errors for Panel Data with multiple groupings

I have a Group-Firm-Year panel data set (i.e., multiple firms make up a group). Suppose I have exogenous variation at the group level over time. In a panel regression with firm and time fixed effects ...
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Can I Use the loo function to help me choose between a Poisson and Bernouilli distribution in bayesian

I have two models exactly similar, but I’m using a Poisson distribution for one and a Bernoulli distribution for the other. Can I trust the information coming out of loo to help me choose? The ...
1k views

Equivalence test for binominal data

I want to apply an equivalence test on my sample to infer whether they are equivalent or not. Since my data are bionominal [0,1] I don’t know whether the TOST procedure (tost() in R) can handle my ...
10 views

Meta-analyzing incidence (count) data with many zero cells

I am conducting a meta-analysis on the incidence of a rare event. I have 15 single-arm studies with events occurring in only 2 studies. The metarate function in the meta package allows for meta-...
357 views

Up to what number of distinct values should I transform a categorical variable in a dummy variable?

When working with categorical variables, it's common to do some sort of transformation. Usually people apply a one-hot encoding. Putting it simply, we transform a categorical into a dummy variable. ...
83 views

Expected value of the parameters in linear regression (trying to understand which part is constant and which isn't and why)

I'm studying Linear Regression and trying to proof/demonstrate some properties of the parameters. When I started working with the expected value of the slope, I got confused with something. I actually ...
7 views

Max number of vote per person [closed]

Population = 75 4 cnadidatets for election Each voter may choose to cast 1 2 3 or 4 votes. Max 1 voter per candidate. What is the max possible # & % of vote per candidate ?
247 views

objective function oscillating in learning for h2o deep net

I'm using the R h2o package for building a deep net with three hidden layers. When inspecting the model object, I'm noticing the training RMSE fluctuates as a function of number of epochs. I'm ...
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Compare regression coefficients across two (or more) svyglm() models

The question I have is related to this one, but slightly more specific. Suppose I use data from a large-scale educational assessment to investigate how students' proficiency in math depends on their ...
8 views

Solving Linear Regression numerically by optimizing Likelihood of errors ~ N(0, sigma^2). What value to use for sigma?

I can solve a linear regression numerically by finding the beta that maximizes the log-likelihood of the residuals distributed N(0,sigma^2). I can do this in Excel using Solver and any reasonable ...
9 views

Applying ranking weights to quantitative mixed-method data?

I have a dataset where some participants were timed doing a task 5 different times with 6 different devices. I want to run a mixed methods ANOVA to find out the mean time differences between the 6 ...
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What is meant by relative frequency in calibration curves

After reading docs on scikit learn on the probability calibration there's couple concerns that bug me. I don’t really understand how the curve values are calculated (y-axis) namely the frequencies. ...
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Unsupervised anomaly detection and classification with event (log) data

I am trying to detect anomalies in a large set of user log events, where most users would be considered “good” and a small minority would be considered “bad.” There are hundreds of event types, which ...
2k views

SVC doing great on validation & test data but scored very low on predicted data

First of all, this is my first machine learning project after taking Andrew Ng's course, so please bear with me. I'm working on the most famous dataset, the Titanic data. First, I split the dataset ...
9 views

Ridge regression - prove derivate is zero at Q* [closed]

How to I prove that the optimal point in L2 ridge regression will make the derivative 0? It's kind of reverse work( I've substituted the q* value in the gradient but not able to prove its 0. L(Q) = 1/...
16 views

Conventions for pmf/pdf

The way I usually see the conventions: for a continuous random variable $X$, the pdf is denoted $f_{X}(x)$ or $f(x)$,where $x$ is an instance of $X$. And for a discrete random variable $X$, the pmf ...
4 views

Evaluating recommender system implicit vs explicit

I have rating data that allows me to create a recommender system based on these explicit rankings. Moreover, I want to test some methods that utilize implicit feedback. I can obtain it by binarizing ...
22 views

Photo attractiveness rating experiment: significance and effect size

I'm a photographer working on a personal project where I experimentally test dating photo advice. I take photos of people under different conditions, changing one variable while keeping others ...
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ANOVA post-hoc correction question

I am currently analysing data from a recent experiment, in which I will perform a 2 way repeated measures ANOVA (exercise intensity [3 intensities] x time [5 time points]). I have a significant ...
703 views

How to evaluate a histogram?

Let's say I have the histogram above which reports performances of some neural networks. The y axis is the bin size, while the x axis is the error, so low errors = high performance. Out of these 15 ...
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Writing PCA as a special kind of auto-encoder

I would like to know if it's possible to view PCA as a particular type of neural network, however, there's one major stumbling block that I haven't yet been able to get past. Define the following "...