1
vote
1answer
33 views

How to present a large dataset of polynomial multivariable regression in a useful format

I've produced a large dataset of results from 3 variable inputs. eg: x1, x2, x3 -> y y(x1,x2,x3) I've gone over the problem logically and it was clear the problem was non linear. To this end I've ...
2
votes
1answer
27 views

Logistic regression when some variables are measured just for a subset of samples

I have been asked an interesting modelling question by a clinician. The outcome he is trying to predict whether a particular type of cancer will occur. One of the covariates is an indicator variable ...
0
votes
0answers
31 views

Proving that Markov Chain Monte Carlo converges

I actually asked the same question in http://math.stackexchange.com/ as well at http://math.stackexchange.com/questions/753105/proving-that-markov-chain-monte-carlo-converges but since the question is ...
0
votes
0answers
23 views

Cannot do Tukey test in multcomp

After performing series of linear mixed models in lme4 to justify which model with which level of interaction to be used, now I would like to do the Tukey's test for multiple comparison. So first, I ...
1
vote
0answers
20 views

Problems with curve fitting

I have a longitudinal dataset to which I am trying to fit the following model : $$ y_{i,j} = \frac{1}{1+a_{i} \exp(-r_{i}t_{i,j})} + \varepsilon_{i,j} \tag{1}$$ The setting : $i$ ($1 \leq i \leq ...
2
votes
2answers
65 views

Treating ordinal variables as continuous for regression problems

In the social sciences I have encountered that it is common to treat ordinal variables as continuous, for example variables originating from rating or Likert scales (strongly disagree, disagree, ...
1
vote
1answer
48 views

Combining summary statistics

Currently I add Var1+Var2=VarSUM12 and then perform a linear regression on VarSUM12~x to obtain test statistics for x and get insight into weak associations that are present across Var1 and Var2 with ...
0
votes
0answers
6 views

Extract Rules from Matlab Classification Tree

I am using Matlab's ClassificationTree.fit to generate a classification tree for my data. Let's say I type: ...
0
votes
0answers
38 views

Linear programming problem [on hold]

You're given 3 puncts of producery $A_1=138$, $A_2=102$, and $A_3=120$, and 4 puncts of consumery $B_1= 120$, $B_2=105$, $B_3=90$, $B_4=135$. Sort the stocks in a way that the necessity of $B_1$ to be ...
1
vote
0answers
17 views

Can I estimate Variance of Gamma from Negative Binomial distribution distributed data, given NB is Gamma-Poisson compound

I believe the data I have follows Negative Binomial distribution (over-dispersed Poisson). We know Negative Binomial is a Gamma-Poisson compound distribution. The variance of this Gamma distribution ...
0
votes
0answers
14 views

Two-way interaction: interpret output from LMM in lmer

I have asked a question in this topic relating interpreting two- and three-way interactions in this link: How to interpret 2-way and 3-way interaction in lmer? ...
1
vote
1answer
21 views

How to perform this ANOVA?

I am interested to know if we have 3 dependent variables, and 2 independent variables, online and face to face, with 2 levels each, as in the example below. The sample size is 30 for each mode of ...
0
votes
1answer
23 views

Analyzing relationship between two Likert-items (is it possible?)

I am a student and am new to statistical market research. Is it possible to analyze the dependence of answers to one Likert-type item on answers to another Likert item (predictor)? If so, what test ...
1
vote
1answer
31 views

How does the interpretation of main effects in a Two-Way ANOVA change depending on whether the interaction effect is significant?

As far as I can tell this question has never been asked before. There are several questions that touch on related issues, but as far as I can see none of them have provided a definitive answer to this ...
0
votes
2answers
28 views

Feature selection with SNP datasets

I'm working with a Single-nucleotide polymorphism (SNP) dataset with over 2.2 million features and roughly 2000 samples. I wish to do feature selection on this dataset to reduce it down to ...
1
vote
0answers
9 views

Is mRMR feature selection sensitive to imbalanced dataset?

I wish to perform feature selection on a dataset using mRMR but my classes are imbalanced roughly 3:1. Should I down sample the majority class or use the whole dataset? If I use the whole dataset will ...
0
votes
0answers
12 views

Probability of class membership given univariate normal distribution

Assuming a class is well described with a normal distribution of u and s, is it reasonable to calculate the probability of membership as: $Pr(x)=Pr(|x-u|)=2.0*\text{cdf}(|x-u|,s)$? I've briefly ...
2
votes
2answers
42 views

Finding a statistically different proportion

I have the following problem: given a proportion $p_1=\frac{X_1}{n}$, where $X_1$ is the number of succesful outcomes in $n$ tries ($X_1$ and $n$ are both > 100), I have to find the smallest ...
1
vote
0answers
12 views

Existence of co-variables

In a study, there are 3 independent variables (A, B, C). I want to manipulate only (A, B). The idea of not manipulating variable C is for it not to interfere with the other two manipulated variables ...
9
votes
2answers
431 views

If I'm not interested in the interaction, is there any reason to run a Two-Way ANOVA instead of two One-Way ANOVAs?

I mean any reason aside from the convenience of being able to complete the analysis within a single procedure.
0
votes
1answer
40 views

Is “A person from Group X was 3 times more likely than a person from Group Y to have the disease” an accurate gloss of an odds ratio of 3?

All the interpretations I've seen have referred instead to the odds being 3 times higher in Group X. However, It is not clear to me that there is a meaningful difference between these formulations. ...
2
votes
1answer
69 views

Hypothesis testing on Poisson Binomial distribution

Imagine $N$ baskets each filled with a different number of products chosen from a set $P$. It is possible to have repeated products in the same basket. For instance: ...
0
votes
1answer
25 views

Change in output depending on mirt version

I have a matrix which I'm trying to run through the mirt function of the mirt package: ...
1
vote
0answers
29 views

Rough estimates for training time of deep belief networks

I'm still learning about deep learning. However I'm currently interested to know if deep learning architectures scale well or not. Suppose I have a dataset with 1 million training examples, can you ...
1
vote
0answers
26 views

Why would I want to use my data this way, and what am I supposed to do with this regression?

I'm writing an essay on the effects of M&A announcements on stock prices. I understand most of the requirements perfectly fine, but I'm stumped on one particular part of the essay. I have for ...
1
vote
1answer
41 views

How should you fit ANOVA and linear regression models, if the equal variance assumption is violated?

This is my topic for the paper I'm working on for an undergrad stats class. It's supposed to be 20 pages... and I'll be honest, I understand very little beyond the basics and am over my head. From ...
0
votes
0answers
10 views

Why feature maps are indexed by two indices?

I'm reading about convolutional neural networks. As I understood a feature map is a set of neurons (i.e like a single hidden layer in traditional ANN). So why feature maps are indexed by (i,j)? ...
1
vote
1answer
61 views

Piecewise regression

I have a time series where I want to fit a piecewise regression equation. Now the problem occurs when I try to fit equations of different degree in different segments of the series. Please provide me ...
0
votes
1answer
16 views

Is mixed logit simulation appropriate for categorical data which include likert ratings?

I have data from a study where subjects were shown videos and asked to identify the contents as one of two options, as well as to rate their confidence of correct classification on a likert scale of 1 ...
0
votes
1answer
12 views

Converting SAS EWMA code to Python

I have the following SAS code that uses PROC FORECAST that I would like to replicated with the Python Pandas pandas.stats.moments.ewma ...
1
vote
0answers
22 views

Expected mean square of random effect in CRD model

Random effect in CRD model: \begin{align} y_{ij} &= \mu + \tau_{i} + \varepsilon_{ij} \\ \tau_{i} &\sim \mathcal N(0,\sigma_{\tau}^2) \\ \varepsilon_{ij} &\sim ...
1
vote
0answers
33 views

Posterior Density in R

I'm new to the site, and to Bayesian statistics and was hoping to get some help. I'm currently working through some study exercises and am required to compute the mean and variance of the posterior ...
2
votes
0answers
27 views

Which steps have to be done before fitting logistic curve to time-series?

I want to cluster time-series concerning sales of products. In the database I have 26weeks after launching each products and units sold each week. One of the method of clustering is to cluster ...
0
votes
1answer
32 views

Determining order of AR model

Suppose that we have the following model $$ y[t] = A_1\sin(\omega_1 t+\phi_1)+A_2\sin(\omega_2 t + \phi_2)+ \cdots + A_p \sin(\omega_pt + \phi_p) + z(t) . $$ Let us call this signal as B. Then in ...
2
votes
1answer
17 views

Measured variables in R's lavaan

I am running a SEM on lavaan in R. The model consists of latent variables [N1 to N3], two dummy choice variables [du1 and du2] and measured satisfaction variable [SV] (besides the measurement ...
2
votes
0answers
67 views

How to get the regression from a plot?

I have a dependent variable C and an independent variable VPT. VPT is the average volume per ...
0
votes
1answer
27 views

Considering correlation of independent variables in regression model

I have one dependent variable C and four independent variables: S SD ...
1
vote
0answers
17 views

Simplified table for computing higher order cumulants

I'm looking for a simplified table that shows how to compute the cumulant cum(x1, x2, ... xn) for multiple variables, n > 4. I know that the 2nd and 3rd order cumulants are equivalent to the compound ...
2
votes
1answer
51 views

plotting part of data using violin plot and the other part as stripchart (stripplot)

I an trying to plot 6 groups, in which 3 has a good amount of counts (ranging from 20 to 400) and the rest 3 have very small counts (1 to 9). I want to plot the distribution of a continuous variable ...
0
votes
0answers
12 views

Confirmatory factor analysis about technology acceptance model in R

I tried to do a cfa with lavaan package in R. I'm not sure, if SO is the right stackexchange plattform, if mathematics fits better just tell me and i will move it. Here is my model: I know how to ...
4
votes
2answers
238 views

Expected sum of money

There is a little problem in the working on this one I have encountered recently. Here it goes: Starting off with \$100, when you toss a coin, if there is a tail, you will get \$10 and lose $10 if it ...
0
votes
0answers
15 views

Confirmative Factor Analysis with R lavaan

i tried to do a cfa with lavaan package in R. I'm not sure, if SO is the right stackexchange plattform, if mathematics fits better just tell me and i will move it. Here is my model: I know how to ...
1
vote
0answers
49 views

Reading the output from a GLMM run in R

I am a complete novice and dummy when it comes to statistics so I apologise in advance... I have been asked to report the results of my GLMMs (I ran two) in a table. This table must state: effect, ...
0
votes
0answers
21 views

Retrospective case study and inferential statistics

I am carrying out some research and am a novice to statistics, having done a 2 week module primarily focusing on parametric data and experimental design. However, for my research I am doing a ...
0
votes
0answers
10 views

Rpart and tree models — cross validation beyond cp value

I normally cross-validate my tree-models (rpart) only on cp-value, e.g. by using caret or xpred or the internal rpart cross validation function. However, there are other rpart parameters -- for ...
1
vote
1answer
24 views

How to value comparative Likert results

I have absolutely no knowledge of statistics. My question is how to make sense of some evaluation results I received. The attached graph represents my results of a Likert question compared to my ...
23
votes
8answers
2k views

Help me calculate how many people will come to my wedding! Can I attribute a percentage to each person and add them?

I am planning my wedding. I wish to estimate how many people will come to my wedding. I have created a list of people and the chance that they will attend in percentage. For example ...
0
votes
0answers
9 views

Performing CFA & Structural Models

I have developed a conceptual framework based on literature. The conceptual framework comprises antecedents and consequences. The antecedents factor 1, factor 2 and factor 3 affects factor 1 and ...
0
votes
1answer
32 views

Interpreting a significant 2-way interaction with post-hoc tests

I'm analyzing reaction time data from a repeated measures ANOVA with the following design: Factor 1 (between-group): GROUP (controls, clinical) Factor 2 ...

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