0
votes
0answers
17 views

Confusion about nonlinear transformation of gamma and inverse-gamma distributions

I have a question about the variance of a transformed random variable, illustrated by a particular example. Let $X_1, ..., X_n$ and $Y_1, ..., Y_n$ be independent random variables drawn from an ...
0
votes
0answers
10 views

How to fit raw signal

I think this is simple, but somehow it's not working. I'm trying to fit my raw data so that basically I end up with beautiful 1 peak. I tried butterworth filtering, Gaussian fitting, a combination of ...
1
vote
1answer
32 views

Can I use bootstrapping in this situation?

I'm faced with a situation where there are few observations of a life insurance product in some cells, where the observations are deaths. The problem is that I need to calculate standard deviations ...
0
votes
0answers
13 views

Benchmarking Software Exercises

I am building a website for practicing programming in various languages. The content is user driven; some users write exercises with test frameworks for validating solutions, and other users write ...
0
votes
0answers
10 views

Using all the data for a decision tree prediction

When doing regression analysis with training and test sets, I would fit the model to the training data. When happy with the model fit I'd then run it against the test/holdout set to get a true ...
0
votes
0answers
14 views

Covariance for a multivariate Bayesian Additive Regression Tree

Chipman, George, and McCullogh (2010) state that: One can also extend the sum-of-trees model to a multivariate framework such as: $$ (29) \qquad\qquad Y_i = h_i\left( x_i \right) + ...
0
votes
1answer
47 views

Post-hoc tests for 2x2 ANOVAs (Type II & III) with interactions in R

I am trying to analyze data from an experiment using R and ran across a problem regarding the use of post-hoc tests with Type II & III ANOVAs. I only know of R functions that perform post-hoc ...
0
votes
1answer
27 views

Linear Regression Percentage Increase/Decrease

I am trying to find out a way to display the percentage increase or decrease to my customers using y = mx + b ...
3
votes
1answer
23 views

Residual Plots and Transformations in Linear Regression

What does it typically mean when the plot of residuals vs. fitted values in a linear regression forms a parabola symmetric about the y-axis (for both convex and concave parabolas)? How can one infer ...
2
votes
0answers
9 views

Significance test for longer pronounciation

I have a set of words spoken by a group of native speakers and a group of non-native speakers. In each record I determined the length of the burst (a phonetic term). I believe non-native speakers tend ...
3
votes
0answers
14 views

Interpretation of log transformed predictor in negative binomial regression

I mainly want to make sure that I'm making the correct interpretation here. I built a negative binomial regression model predicting a count variable. There was evidence of overdispersion or I would ...
0
votes
0answers
25 views

predicting hour of the day [on hold]

What would be a good model to use to predict hour of the day. For example, I'd like to predict hour of the day when a person will use transportation. sorry for not being clear! This is the header ...
2
votes
1answer
19 views

Chi-Squared Goodness of Fit Test Alternative? - Zero Can't Be in Denominator

I have 5 zones(categories) in which a certain percentage of total sinkholes exist. I have 5 different maps that I am testing to see which one provides me with the best fit to my expected percentages ...
1
vote
1answer
22 views

Percentage with Normal Distribution

Based on the picture below, there is a value with a percentage that is 68 and 95 percent in relation to standard deviations in a normal distribution. My question is: What do the 68 and 95 percentages ...
0
votes
0answers
5 views

About Chi Square Statistic Table [on hold]

I do not understand relation with The Chi Square Statistic table based on the link above. Why and how can it be "2.706" och "3.841"? I understand why it will be Df 1 but ot for the column 0.10 ...
1
vote
0answers
27 views

Is the chi squared test appropriate?

I have claim data from two different insurance administrators. From each administrator, I have calculated the relativity of miles driven per year based on claim data. I want to determine whether ...
1
vote
0answers
11 views

Plotting raw data, but running statistics on log-transformed data

My data is non-normal, I want to show my raw data, in a scientific journal, by median +/- mad, to show the true nature of the data. However, if log-transformed, the data is normal. Can I then ...
0
votes
0answers
19 views

Bar plot with median +/- median absolute deviation in scientific publication

I know bar plots usually represents mean +/- sem, but if the data is non-normal, is it ok to bar plot median +/- mad? I don't like box plots. Suggestison?
0
votes
0answers
13 views

What statistical test(s) should I run to analyse a directed-tree like data?

Suppose I have data of a kind of binary tree format. There are three levels in the three, thus four different leaf nodes. I would like to find the optimal path from the root node to one of the leaf ...
0
votes
1answer
49 views

Machine learning - curve categorisation

I have curves of the following structure (it is the blue one I am interested in) These curves reflect the volume of blood (actually gamma ray counts) in the left ventricle as a function of time ...
0
votes
0answers
20 views

Plot 2D view of 3D joint ecdf with isolines

I have this matrix, histDict, which is a dictionary of data of variable X for each value of variable ...
3
votes
3answers
46 views

Simulation from linear model with additional variables

I want to test the performance of a variable selection method in linear regression with normal errors using simulated data: $${\bf y}= {\bf X}{\bf \beta} + \epsilon,$$ where, as usual, ${\bf y}$ is ...
0
votes
0answers
15 views

Factor analysis: what are the total possible scores for calculated factors based on Likert scale responses?

I have two factors, Peer Social Interaction (PSI) and Sense of Belonging (SB). Four Likert scale questions correspond to each factor. I used the factor loadings for each question to create a ...
0
votes
0answers
13 views

Discrete optimization with a very large solution neighborhood to explore

I have a problem whose feasible (discrete) solutions can measured by a cost function. I am thinking of using some optimization technique to get better solutions from a rough initial approximation. I ...
0
votes
0answers
35 views

R- Improving linear regression fit

I am trying to construct a predictive model in R. I am using the glm() in R to fit the model. I am getting a very high residual error after fitting the model. My target values are in the range of ...
0
votes
0answers
14 views

Category prediction in ordinal regression

This could be a naive question. I have three slabs for my dependent variable and when I run the ordinal regression the predicted responses are in first and third slab but no observation is predicted ...
2
votes
2answers
46 views

Confidence interval for $\eta^{2}$ for MANOVA in R

I have to report the Confidence Intervals for the $\eta^{2}$ obtained in a MANOVA in R. I use the function etasq of the package heplots to obtain the $\eta^{2}$. ...
0
votes
0answers
21 views

Best size for control in Control/A/B/C/D split test

I'm doing some split testing on a website, and have multiple tests running along with a control. Say we have control/A/B/C/D. If we only had control/A, then I know I should make them both the same ...
0
votes
0answers
32 views

Determine if regression results are significantly better with method A or method B

I'm working on a regression case and I am using two methods, lets say method A and B. Due to the randomness in the optimisation techniques of these methods the output will always differ slightly. ...
0
votes
1answer
20 views

Inverse-variance weighting

I'm writing a Bachelor Thesis in engineering an a small part of it has two deal with assigning weights to independent measurements. This is from the thesis: I am pretty sure that what equations ...
0
votes
0answers
56 views

Statistical publishing - english majors? [on hold]

This is a statistics question. Really. I have several topics that I would like to publish. While I can get a paper, in technical terms, 100% of the way done I am not an English major. I don't do ...
1
vote
0answers
18 views

Calculate statistical power on groups with different size

Is it technically possible to calculate the statistical power for a test where the two groups don't have by design the same size. I'm thinking to a 90%-10% split of the population. Namely, is there a ...
1
vote
1answer
24 views

How to compute RMSE for TBATS

Some forecasting models in R give error terms as their output. But for TBATS, I couldnt find out that how I can see what the RMSE for my data set is. Is there any specific command that I have to use ...
0
votes
1answer
26 views

Statistical Commute Analysis in Java

I have a rather large commute every day - it ranges between about an hour and about an hour and half of driving. I have been tracking my driving times, and want to continue to do so. I am capturing ...
0
votes
1answer
20 views

Data with weekly and annually seasonality but the first day in time series is not the begining of a week

I know it might look naive but I have a very basic question. I have a three years of historic data which has weekly and annual seasonality. January first as my first data is on Wednesday so my time ...
-1
votes
0answers
30 views

Is there any difference between consistent statistic (outcome) and consistent estimator? [on hold]

Wikipedia and SE questions talk about consistent estimator. Interestingly, consistent estimator has been preconditioned as sample-size increases. We should talk about consistent estimate (statistic) I ...
0
votes
2answers
30 views

ROC (Epi library) how to calculate TP, FN,TN, FP

I'm trying to find how to compute the true negative (TN), false negative (FN), true positive (TP), and false positive (FP) if I have a cutpoint like in the following picture: ...
1
vote
3answers
88 views

What probability distribution best describes my data?

I have a variable whose values are summated scale scores with values ranging from 3 to 21. I considered this variable as a scale variable (though with restricted range). In order to model the relation ...
0
votes
0answers
6 views

regression test or two bloc PLS model to prove a gene expression matrix relationship

I have two gene expression matrices, matrix A coming from a set of two hypothetically different cells while matrix B is coming (for certain) from only one of them. The structure of a gene expression ...
1
vote
0answers
11 views

Odds Ratio in 2*3 Table

How can calculate Odds Ratio in 2*3 Table ( Participante [case -control] and marker [genotype])?
-1
votes
1answer
25 views

Distribution of sum of two shifted Poisson

Suppose Y is shifted Poisson at "a", say Y -a ~Poisson (t) and X-b ~ Poisson (r), again a shifted Poisson at "b." Now what is the distribution of Z= X+ Y? Any idea? How to prove it?
1
vote
0answers
18 views

Using multinomial testing with 3 outcomes

I am a little lost on how to do a multinomial testing with 3 outcomes, where i want to calculate the probability of success based on following data: Success: $p^1 ...
0
votes
1answer
21 views

Difference in rules via apriori() with target “frequent itemsets” and ruleInduction() and via apriori() with target “rules”

Regarding R package arules: To my understanding the Apriori algorithm works by first finding all frequent itemsets that meet the support threshold and then generate strong association rules from the ...
0
votes
0answers
13 views

Need to transform data before running mediation/model with bootstrapping (PROCESS)?

I am reading through Hayes' book on mediation and moderation analysis (2013) which describes the PROCESS macro he created to use bootstrapping in order to arrive to confidence intervals to check the ...
0
votes
0answers
12 views

Pareto two-tailed GLM regression

How can I perform a Pareto two-tailed GLM regression? Any reference to link functions and code in R?
2
votes
1answer
102 views

maximum-likelihood of a sequence of events described by a Bernoulli distribution

I am having quite some troubles with the following homework: In a city it's measured for the whole year whether it rained or not. A distribution $\textrm{Bernoulli}(r_t|\rho)$ characterizes the ...
0
votes
0answers
14 views

Selecting variables in an SPSS-file (*.sav) using R [on hold]

I'd like to use a SPSS file (European Values Survey, to be more precise) in R. Specifically, I want to select certain variables (a country, a certain question [trust in armed forces] and the ...
0
votes
3answers
37 views

Simulate data for 2 x 2 ANOVA with interaction

What is the best way to simulate ANOVA data for a 2 x 2 design with interaction using a regression approach? I want to generate the data so that I know the true regression coefficients of the model ...
0
votes
0answers
9 views

CHAID influence variable

I am trying to do a decision tree analysis (CHAID) and I would like to know what "influence variable" means in its method. Several researchers do not use an influence variable whilst others suggest ...
1
vote
1answer
19 views

Correct specification of HLM in lmer

I originally learned about random effects models when taking a course on Hierarchical Linear Models, which was taught using Raudenbush and Bryk's HLM book and software, and it sort of indoctrinated me ...

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