A statistical model is a formalization of relationships between variables in the form of mathematical equations. A statistical model describes how one or more random variables are related to one or more random variables. The model is statistical as the variables are not deterministically but ...

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34 views

Do women seeking a long-term mate prefer men who can provide resources for her offspring? [on hold]

I have to design a study on whether or not women seeking a long term mate will prefer men or a man who can provide resources for her offspring. I'm not sure where to go with this. Any advice or ...
0
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0answers
7 views

Filling incomplete data & forecasting in multivariate time series per kalman filter

I have a large set of timeseries, some with missing values. I want to fill in missing values. A given missing value in a column should be filled up conditional on the contemporaneous value of all ...
0
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1answer
19 views

How to test repeated, nested, count data

I have samples from an experiment in which I have counted cells. I took 2 pictures of each kidney, photographing both kidneys of each subject. Each individual belongs to a group (infection). My ...
0
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0answers
20 views

Assessing calibration plot

I am curious about calibrating a probability estimate, namely a logistic regression. With the example below the outputted calibration plot shows bad calibration with the estimate, or the non ...
0
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0answers
10 views

Improve ctr for recommender system

I work in internet advertising company and the task is to increase ctr. I have different variables, such as amounts of clicks, user location, browser, os, his previous history etc. What are possible ...
0
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0answers
26 views

Conflict answers between SPSS and R Software [on hold]

I used R software (auto.arima function) in getting the best ARIMA model for my data. Then I used SPSS in getting the parameter estimates since there is no p-value ...
0
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10 views

Dynamic regression models in SAS

Could anyone please advise on any relevant material on utilising dynamic regression models in SAS? The response variable is a continuous variable with multiple drivers with various types (categorical, ...
0
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0answers
13 views

Analyzing frequency of medical procedures by hospital and patient characteristics

I'm working with state-level HCUP data. This mostly includes patient characteristics (age, gender, race, etc.), diagnoses and procedures, as well as info on the hospital including bed size, ...
0
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0answers
25 views

A time series which cannot be made stationary

I have a series of data points, of days between successive earthquakes. I am trying to model time between earthquakes, in order to predict waiting times. Using Minitab I have tried differencing, ...
3
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1answer
49 views

How to find “theoretically best” model?

Given the common problem of predicting response variable $Y$ from predictor variables $X$ and $Z$, is there any way to determine the "theoretical best" prediction possible for a response variable? ...
0
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23 views

Measuring change in performance over time

I have two performance scores for multiple companies over a ten year period (10 sets of scores, one set for each year). Which would be the best method to test the hypothesis that one score has dropped ...
0
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0answers
6 views

Node dimension does not match in WinBUGS [closed]

I'm using WinBUGS14, though I am not adept at it. I have worked through several problems before, however, this error seems to be tripping me up. Node dimension does not match This EXACT code has ...
0
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2answers
25 views

Methods for modeling discrete dependent variables and categorical independent variables

I need to determine if there are relationships between discrete dependent variables and categorical independent variables. To give some examples, one discrete dependent variable would be salary and ...
0
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0answers
20 views

Fitting a model with time of day, day of week adjustment

I have one year's worth of clickstream data (like Minute, Numvisitors). I'm trying to see whether external events (commercials) affect ...
3
votes
2answers
42 views
+50

Next Best Product Modeling (Seeking reference material)

I am being tasked with developing a "next best product model", and at this time, I can safely say that I do not know where to start! In other words, I want to develop a model that will provide ...
0
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0answers
21 views

Multiple categorical outcomes in R

I am trying to associate clinical signs with three disease outcomes. I have a list of 30 signs, each of which are a binary factor (present or absent, 1 or 0) as well as a few patient demographic ...
3
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3answers
73 views

How to best model interaction effect of two continuous predictor variables?

Consider the following problem: In a logistic regression model, we believe that two continuous predictor variables $X_1$ and $X_2$ impact the probability of event. It is hypothesized that the ...
0
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0answers
16 views

Framework/tool for scalable automatic model training in batch and online?

For a retail problem, we need to build model for every individual customer on their accumulated historical data on a periodical basis. This is to predict certain classes individually. For a ...
0
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0answers
99 views

Email open-rate optimization

I am trying to maximize open rates of emails by selecting between two subject headlines {h1, h2} for a marketing campaing. The hypothesis is that different customers react to different headlines. ...
0
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0answers
20 views

Adding variables in multiple linear regression

Pretend that I had a MLR consisting of $Y=a+b$ and I wanted to add a new variable $c$ or $d$, but not both. So I would either end up with $Y=a+b+c$ or $Y=a+b+d$. I know I can run the regression on ...
2
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1answer
89 views

VAR forecasting methodology

I am building a VAR model to forecast the price of an asset and would like to know whether my method is statistically sound, whether the tests I have included are relevant and if more are needed to ...
0
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0answers
20 views

Why SVR kernels other than 'linear' don't work for this toy dataset!

I'm a little new with modeling techniques and I'm trying to compare SVR and Linear Regression. I've used f(x) = 5x+10 linear function to generate training and test data set. Here we've discussed why ...
0
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0answers
27 views

How to improve the model of a fit to a sinus modulated sinus

I am trying to determine the amplitude of a sinus modulated sinus as accurate as possible. My sampling frequency is sufficently high and I am currently using a LSQ fit. The entire model looks as ...
1
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0answers
23 views

Is there an appropriate way to control for individual subject identity in a linear model when data points arise from pairs of subjects?

Is there an appropriate way to control for individual subject identity as a Random effect in a linear model if each data point arises from a pair of subjects (for example, how long it takes two ...
1
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0answers
22 views

How to calculate influence of variables at ROW LEVEL?

There are several algorithms which give relative importance of variables at OVERALL Model level. But the most influencing variable might not be the reason why a particular row might get higher or ...
1
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2answers
37 views

Subset selection features acquired from randomized logistic regression

I learned about the concept of randomized logistic regression(or randomized lasso) recently. My data, biological data called Microarray, usually has large features but small samples - 10000 features ...
0
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0answers
17 views

How to scale two models build for two different parts of the same data set the way I can bind the predictions and use them as one final model?

I have a big data set where two models have been built. Every model is used to make predictions of some part of the data, but I want to measure how the two models combined are working in the whole ...
0
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0answers
13 views

Survival with unknown birth time and large observation time resolution

Suppose at $t=0$, we have a box with nothing in it, then 8 hours after at $t=8$, we ook in the box and find inside $N$ cells that have appeared. Over these $N$ cells, $D$ are dead and $L=N-D$ are ...
0
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0answers
34 views

degrees of freedom from empirical sum of squares

I am quite new to all this and would greatly appreciate some guidance. I have the following situation: I have count data (y- values) for x- values between 0 and 100 from an experiment Z This count ...
1
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0answers
17 views

Statistical support to aid setting weights in a simple function

I'd like to create some consensus scoring function that incorporates two independent scoring functions $f_1$ and $f_2$. These functions rank items $i$ where there are $i=20,000$ items. $C_i = (f_1 ...
1
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0answers
19 views

NOE Model and Hammerstein-Wiener Model Similarities in System Identification

A nonlinear OE Model is defined as such: \begin{align} \hat{y} &= g(\phi(t)) \\ \phi(t) &= (u(t), u(t-1), ..., u(t-n_u), \hat{y}(t-1), ..., \hat{y}(t-n_y))^T \end{align} where $g$ can ...
0
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0answers
25 views

Analyzing classification model errors

Mine is a classification problem where I have 153 observations. There is a categorical dependent variable (DV), which can take values of either "0" or "1". And there are 15 independent variables, ...
7
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3answers
478 views

Statistical Independence in the real world

I read the following article about statistical independence. In summary, the article argues that "It is time for science to retire the fiction of statistical independence," and goes on to explain ...
3
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0answers
25 views

Major League Soccer: Taking number of teams per season into account when modeling

Im doing research on the effect of salary inequality on team performance in the Major League Soccer, seasons 2007-2014. So for every season, I have data of all the salaries of all the teams, so I ...
0
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0answers
12 views

Designing the Model Matrix for Modeling

I have a question on dataset design for model creation.The problem comes with one hot encoding, where a categorical variable gets converted into N-1 binary columns. However what if in my sample, a ...
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1answer
71 views

Replacing Variables by WoE (Weight of Evidence) in Logistic Regression

This is a question regarding a practice or method followed by some of my colleagues. While making a logistic regression model, I have seen people replace categorical variables (or continuous variables ...
0
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0answers
20 views

Replacing Variables by WoE in Logistic Regression

This is a question regarding a practice or method followed by some of my colleagues. While making a logistic regression model, I have seen people replace categorical variables (or continuous variables ...
1
vote
1answer
57 views

Forecasting and making sense of data

This might seem very elementary or even silly, but all comments are much appreciated. As science major I do not have deep technical knowledge in statistics, so any guidance is much appreciated. Say ...
0
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0answers
11 views

Appropriate model to score a test dynamically?

I have a test bank of questions with particular difficulties (say, a number from 1 to 10), and people take "tests" consisting of some subset of those questions. Each question is graded on a 1 to 10 ...
0
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0answers
18 views

pre-whitening ARIMA order of integration

I am currently modelling a time series using an ARIMA model with transfer functions for the regressors. In order to get a stationary dependent variable I need to take seasonal differences (at lag ...
0
votes
1answer
25 views

machine learning with asymmetric training data frequencies

I have about a million rows of data being collected every day, and I am trying to predict a government figure which is released on a less frequent basis, about once a month. Compared to a traditional ...
1
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1answer
27 views

Prediction or forecast error

I understand the general idea of different time series model fittings, calculations, and model comparison. However, I am a little confused of understanding the forecast of a time series model. For ...
0
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1answer
111 views

Checking the goodness of a probability model

I have a data set that I claim is adequately modeled by a probability distribution, or more generally a family of probability distributions. How do you decide that the model is good/useful/correct ...
3
votes
1answer
59 views

Importance of variables in RandomForest in R

I'm using varImpPlot() to evaluate the importance of variables from my rf model, and I can't decide wich variable I have to delete from my model. I'm not sure about the diference between ...
0
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0answers
13 views

How to model discrete co-occurence data

I have a dataset of transactions where in each transaction a class is tagged with a number of labels. I would like to build a probabilistic model using this data to determine given a class how likely ...
1
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0answers
30 views

Random Forest and Binary logistic regression (with quasi-complete separation issues)

I am working on a data set (n= 230) with a categorical dependent variable (outcome: 0/1) and six categorical independent variables (mostly, with only two levels). There is a certain degree of ...
0
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0answers
9 views

Basis for fitting a complete monotone

I have set of measured data: x=[x1,x2,....,xn] y=[y1,y2,....,yn] It is a multi component data. However I need to fit for only one component which is known to ...
0
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0answers
17 views

Standardizing Values to Compare Overall Modelled VS. Measured Results for Multiple Variables

I have a mathematical model that's designed to simulate average values of four different variables in a plant canopy: height, width, density, and height distribution. I ran the model for in a manner ...
0
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0answers
8 views

What model to use?

I have data consisting of percentage of a fruit disorder from 6 different orchards, as well as characteristics of individual fruit from each orchard. The fruit were harvested at 3 different times from ...
13
votes
2answers
209 views

Is prediction the 'golden criterion' to judge the ability of statisticans?

I was reading Faraway's textbook linear models with R (1st edition) last weekend. Faraway had a chapter called "Statistical Strategy and Model Uncertainty". He described (page 158) that he ...