instruction stringlengths 9 38.7k |
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In a simple linear model with a single explanatory variable,
$\alpha_i = \beta_0 + \beta_1 \delta_i + \epsilon_i$
I find that removing the intercept term improves the fit greatly (value of $R^2$ goes from 0.3 to 0.9). However, the intercept term appears to be statistically significant.
With intercept:
Call:
lm(formula... |
I want to create a classification table regarding an ordinal response variable with three levels but I don't know how to do it. Searching on the site I fell on the question posted by Brandon Bertelsen that covers only the case of the binary logistic regression (link at the end of the post).Does anyone knows how I can c... |
I run an ordinal regression model and I wanted to check the proportional odds assumption. In order to do that I used the VGAM package and I run olr twice, the first under the assumption and the second without the assumption. Below is the code and the results
> fit1 <- vglm(stage ~Ki67+Cyclin_E,family=cumulative(paralle... |
I would like to convert an ARIMA model developed in R using the forecast library to Java code. Note that I need to implement only the forecasting part. The fitting can be done in R itself. I am going to look at the predict function and translate it to Java code. I was just wondering if anyone else had been in a similar... |
I'm looking into the Itakura Parallelogram global constraint for Dynamic Time Warping.
I am confused about the maximum width of the parallelogram, is it solely based on the length of the two time series being compared, or can it be varied to achieve a bigger or smaller warping window?
|
I want to estimate the parameters (mean , variance ) $e(t)$ for the random walk model
$X (t) = X (t-1) + e(t)$.
(where $e(t)$ is the white noise with a Normal distribution).
By using the fact that the $E(X(t)) = E (X(t-1))$ mean can be easily proven to be zero. Can someone help me to come up with a formal proof for t... |
After some heavy reordering and canceling of factorials, I discovered that the following experiment is approximately equivalent for $m \ll n < N$ if conducted with or without replacement:
In $n$ turns, draw marbles (with/without replacement) from an urn containing $m$ white and $N-m$ black marbles. Count the white mar... |
I've read that Mahalanobis distance is as effective as the Euclidean distance when comparing 2 projected feature vectors in classification using a LDA classifier.
I was wondering if this statement were true?
It would be nice if someone could comment on this.
I'm working on projecting a 36 dimensional feature vector to ... |
Possible Duplicate:
Properties of logistic regressions
I have built a logistic regression model with two covariates. Let $y_i$ be the binary responses and $\hat{\pi}_i$ the ML estimated probabilities for $i=1,\ldots,n$. Now it happens that $\sum_i{y_i}\neq\sum_i{\hat{\pi}_i}$. So, computing a chi-square goodness of ... |
Is it common practice (and adequate) to regroup two binary dependant variables into a single 4-level dependent variable to take advantage of the multinomial regression? For instance, say we have information on two related conditions (outcomes) A and B. A new 4-category variable would be defined such that:
category 1 = ... |
I have a logistic regression model which predicts win/loss on amount of money paid. I run my model every two hours on new data that I acquire and use it to predict the next two hours. However, I keep finding that my model underpredicts win/loss for each amount of money paid. So I'm in this situation where I have a stat... |
Suppose:
$N \sim {\rm Poisson}(\lambda)$
$\lambda$ is unknown, but we believe that it can be assumed $\sim \exp(1)$
If I want to calculate $N | X$, i.e., $P(model | data)$, I need to use the Bayes theorem in the following way:
$P(model|data) \propto P(data|model)*P(model)$
$P(data|model)$ is the likelihood function
... |
Pretty new to R and to stackexchange. My apologies if I make any faux pas.
I'm working with the North Carolina births data from irss.unc.edu. I have a data frame NCBIRTH1450 with several lists, all of which have numeric or NA values. I'm just trying to calculate some proportions from the data. For one of the lists,... |
I want to generate a bivariate Gaussian dataset. The dataset includes a total of 800 results drawn randomly from four two-dimensional Gaussian classes with means $(-3,0)'$, $(0,0)'$, $(3,0)'$, and $(6,0)'$, all with the same variance-covariance matrix
$$\Sigma = \pmatrix{0.5 & 0.05 \\ 0.05 &0.5}.$$
How can I do that in... |
Here's my experiment: I'm testing the physiological effects of a treatment on a mice (measuring continuous variables such as total mass, fat mass, bone density, etc). I want to test the significance of this treatment on weight gain parameters.
What I've done so far: in R, I've fitted a logistic glm model, using the bin... |
I have found a lot on the internet regarding the interpretation of random- and fixed-effects. However I could not get a source pinning down the following:
What is the mathematical difference between random- and fixed-effects?
By that I mean the mathematical formulation of the model and the way parameters are estimated.... |
Please see edit.
When you have data with heavy tails, doing a regression with student-t errors seems like an intuitive thing to do. While exploring this possibility, I ran into this paper:
Breusch, T. S., Robertson, J. C., & Welsh, A. H. (November 01, 1997). The emperor's new clothes: a critique of the multivariate t ... |
I have been searching on the net for the term dependent and independent samples, but I couldn't find proper definition, nor to conclude what exactly it is. It would be nice if anyone of you could explain it and bestow us with the knowledge.
|
I've been asked to try to do a preliminary 'meta-analysis' of some data, but while comfortable with maths I don't have much experience with stats. I'm hoping to get some feedback with what I have attempted so far, to see if I'm on the right track.
Using SPSS for the software.
Design
One dependant variable 'size' taken ... |
Hi all I have a question. Suppose
$$X(t) = A \cos(t) + B \sin(t)$$
is a weakly stationary process, where $A$ and $B$ are random variables.
Why is it that the mean of $A$ and $B$ are necessarily 0? As I understand it, weak stationarity only requires that the $E(X) = \mathrm{constant}$.
|
I'm analyzing a very large, but not finite, set of survey data. I've assembled a time series crossing gender (2 categories, if there was uncertainty) with age (in 6 categories) and wish to test whether the demographic representation has changed over time. Using the chi-squared test for independence, I understand that f... |
This question is similar to the one posed here:
Testing significance of peaks in spectral density
In that post, Pantera asks how to test whether a peak in a periodogram has a spike that is significantly different from the spikes generated by noise.
My question is this, when using the spec.pgram() function in R, a con... |
Based on a sample of $n$ survival times, I would like to estimate the probability of surviving time $t$, for some specific $t$, using the Kaplan-Meier estimator. Is it possible to do this in R? Please, note that $t$ is not necessarily an event time.
|
I'm reading John Kruschke's "Doing Bayesian Data Analysis" slides, but actually have a question about his interpretation of t-tests and/or the whole null-hypothesis significance testing framework. He argues that p-values are ill-defined because they depend on the investigator's intentions.
In particular, he gives an e... |
Scenario:
Consider a statement, e.g. "This movie is an action"
Then let people vote on that. 1-5 where 1 is "Not action", 3 is "Some action" and 5 is "Pure action".
Question
How does one determine how accurate the the statement from the voting result?
1000 votes where 900 is a 5 is pretty accurate, but 1000 votes with... |
The central difference is a method to approximate numerically the derivative of a function sampled at discrete intervals. In R, one would do:
n<-100
y<-cumsum(rnorm(n))
y_p[1]<-diff(y[1:2])
for(i in 2:(n-1)) y_p[i]<-diff(y[c(i-1,i+1)])/2
y_p[n]<-diff(y[c(n-1,n)])
My question is, what is the comonly accepted inverse to... |
suppose we have a stream of sentences and we need to compare each new sentence with previously received ones . For example , with sentences received in last 30 minutes. What is the best method to do that ? can we use Mahalanobis distance for this ? How ?
|
CLT states in short, that sum/mean of random iid variables from almost any distribution approaches normal distribution.
I failed to find information about asymptotic behavior of sample variance when sample is drawn from unknown distribution. Do we have any reason to believe, that variance of random iid variables asymp... |
In probability and statistics, the concept of "random" and "randomness" are frequently used. Often the concept of a random variable is used to model events that occur due to chance.
My question regards the term "random". What is random? Does randomness really exist?
I am curious what people that have a lot of experie... |
I want to compare the accuracy of two classifiers for statistical significance. Both classifiers are run on the same data set. This leads me to believe I should be using a one sample t-test from what I have been reading.
For example:
Classifier 1: 51% accuracy
Classifier 2: 64% accuracy
Dataset size: 78,000
Is this th... |
What is the politically correct way of ordering stacked barplots that contain gender statistics? For example, in a stacked barplot for the number of grantees of a fellowship program, should one put male or female on the bottom? How about left/right if it's on horizontal bars?
|
I'm testing the cointegration of two time series of stock prices using adfTest from fUnitRoots, but first I need to check if the series are I(1).
How can I check if a time series is I(1)?
|
I'm training some neural networks using NEAT C++, and would like to use the cross-entropy error function:
$$E = -t\ln(y) -(1-t)\ln(1-y)$$
to train a network for a two-class classification problem.
NEAT C++ is a C++ library that allows one to use a special kind of neuro evolution (namely that of augmenting topologies) t... |
Are there functions in R that could help me do the following?
We have a special type of regression which is called Geometric Mean Regression.
We have done some search and found the following:
https://stat.ethz.ch/pipermail/r-help/2011-July/285022.html
The question is: how to do the statistical inference on GMR results?... |
in my ANCOVA analysis, I have the case that my Y and X show a nonlinear pattern. Transforming either only Y or X does not help to stabilize variance. I did not find any hint that doing an ANCOVA in log-log space is illegal, however, I also did not find any note on that one should try out a transformation of Y AND X...... |
What are the standard techniques of plotting a statistical ensemble of sequences?
I know the chaos game representation:
H. Joel Jeffrey (1992), Chaos game visualization of sequences. Computers & Graphics 16 (1): 25-33.
and two-dimensional plots:
H.C. Lee Hao and Shu-yu Zhang (2000). Fractals related to long dna sequ... |
Context:
I’m working with the Census Bureau’s American Community Survey (ACS) data which are samples (not complete enumerations) aggregated at different spatial scales. Each ACS estimate is provided with a margin of error (which is easily converted to a standard error, SE). I’m attempting to generate a regression lin... |
I am working on a project where I am evaluating software packages. I have got the results of two experiments where only one variable has been changed. Each experiment has been conducted 10 times. I am doing paired-sample t-tests. For some of my metrics, the results are exactly the same for the ten iterations. Therefore... |
I'm trying to understand how to interpret log odds ratios in logistic regression. Let's say I have the following output:
> mod1 = glm(factor(won) ~ bid, data=mydat, family=binomial(link="logit"))
> summary(mod1)
Call:
glm(formula = factor(won) ~ bid, family = binomial(link = "logit"),
data = mydat)
Deviance Resi... |
I am in need of a package that can give me the equation for a linear SVM model. Currently I'm using e1071 like so:
library(e1071)
m = svm(data, labels, type='C', kernel='linear', cost=cost, probability=FALSE, scale=scale)
w = t(m$coefs) %*% data[m$index,] #Weight vector
b = -model$rho #Offset
However, I'm not sure ho... |
I have a $10000\times2$ table (see below) where column A is made out of observed data and column B is the output of a model that I have which should fit the observed data A.
$n_{A}$ is the total number of points in column A and $n_{B}$ the total number of points in B and they are not necessarily equal.
A B
-----
1 ... |
As the title goes, does anyone know of a good, up to date book that covers data preprocessing in general and especially outlier detection techniques?
The book doesn't need to be focusing exclusively on that, but it should deal with the aforementioned topics exhaustively - I wouldn't be happy with something that's a sta... |
Lets assume I have collected some data about sold ice creams on the local market on the daily basis. Days( just a number of observations, might be classified otherwise, it's not variable ) present the day collection of data took place, var1 represents sold ice creams between 09:00-10:00, var2 between 12:00-13:00, and v... |
Correlation does not imply causation, as there could be many explanations for the correlation. But does causation imply correlation? Intuitively, I would think that the presence of causation means there is necessarily some correlation. But my intuition has not always served me well in statistics. Does causation imply c... |
I am dealing with 2 class LDA classification problem.
During a test phase (after training), I'm trying to project a feature vector to lower dimensional space.
How do we get the projected test feature vector?
Is it
Y = (X-mean) * W
Y = X * W
Which one of above is true? (X is feature vector, W is weight vector obtaine... |
I've been reading/looking around for literature on support vector regressions that are relatively robust to outliers. I understand that standard SVRs can be significantly influenced by a few large outliers. From what I've read (and I'm no academic to be sure), there appears to be a number of different approaches. My qu... |
I'm not an expert in statistics, but I gather there is disagreement whether a "frequentist" or "Bayesian" interpretation of probability is the "right" one. From Wagenmakers et. al p. 183:
Consider a uniform distribution with mean $\mu$ and width $1$. Draw two values randomly from this distribution, label the smallest ... |
I need help to understand the meaning of the following formula:
$$\sum_{i=1}^n\sum_{j\neq i,j=1}^n(x_i-\mu_i)(x_j-\mu_j)c_{ij}$$
where C is positive semidefinite matrix, $\mu_i$ is the mean of $x_i$.
I was thinking, since $c_{ij}$ is the covariance between $x_i$ and $x_j$, this formula kind of sums up the correlati... |
What methods are there for measuring the strength of arbitrary, highly non-linear relationships between two paired variables? By highly non-linear, I mean relationships that can't sensibly or reliably be modelled by regression to a known model. I'm particularly interested in time-series, but I imagine any thing that wo... |
I have a model file that was created using svmlight in classification mode with a linear kernel. Is it possible to convert this file so that libsvm can use it for classifying?
|
I am running a regression with several independent variables with 32 observations (from 1975 to 2006 and they are yearly data). The issue here is that there does not exist any observation for one of the variables prior to 1980. Consequently, that variable has 5 missing observations (from 1975 to 1979).
Is there any met... |
I have been presented with a dataset comprised of individuals and the number of teeth they have had extracted. The maximum is 32, and almost half of the data are zeros. I have been asked to suggest an appropriate multivariate model for these data.
I originally thought this would be a negative binomial distribution howe... |
I've been reading Wagenmakers (2007) A practical solution to the pervasive problem of p values. I'm intrigued by the conversion of BIC values into Bayes factors and probabilities. However, so far I don't have a good grasp of what exactly a unit information prior is. I would be grateful for an explanation with pictures,... |
Just moments ago, I asked this question because I've been reading Wagenmakers 2007. I now have a better understanding of what a unit information prior is and can push my knowledge further with two (by which I mean 3) questions:
The unit information prior has been considered by some to be too conservative. Are there ... |
I am looking at the relationship betwwen two interval level variables, being income and subjective well-being and I want to test the overall correlation as well as the correlation in three professional groups, namely doctors, high school teachers, and shop assistants.
If I use bivariate correlation, I will have to run... |
Hi Fellow Statisticians,
I have a source generating hashes (e.g. computing a string with a timestamp and other information and hashing with md5) and I want to project it into a fixed number of buckets (say 100).
sample hash:
0fb916f0b174c66fd35ef078d861a367
What I thought at first was to use only the first characte... |
Possible Duplicate:
Derive househould weights from a uniformly distributed person sample
EDIT: Essentially, I have answered the question myself in the linked question: Derive househould weights from a uniformly distributed person sample. I am keeping the text below for reference.
For a finite population $U$, I know... |
I'm currently working on a project involving GLMs (and eventually GAMs) of some count data over time. Normally I'd do this in SAS, but I'm trying to move to R, and having...issues.
When I fit a GLM to count data using the following:
cdi_model <- glm(counts ~ exposure + covariate + month, data=test, family = poisson)
I ... |
I am dealing with a data set containing roughly $n=4000$ binary observations $Y_1, \ldots, Y_n$ with $p=1000$ binary explanatory variables. I suspect that a lot of these explanatory variables are not relevant to the prediction of the observations. Moreover, it is clear that there are certain groups of explanatory varia... |
Background: I have a dataset, which consists of waterlevel measurements over time at different locations. However, the locations are irregularly measured in different years. Therefore my data consists of more gaps than actual data.
Additionally, some of my data is nested. That means that some of my measurements can be... |
If I center my variables and then run a PCA, do I need to interpret negative eigenvectors different than positive eigenvectors?
Clarification: In my PCA I have in a component both negative and positive variables. This is probably very basic, but I've been told different things about the interpretation of the variables ... |
I have a return series of 60 obs. From this returns I compute a non parametric measure.
What is the best way in your opinion to get a consistent estimate of the variance of this measure?
I did it in this way:
I compute a number of X block bootstrap (to take into account of returns dependence) and then for each bootstra... |
Its an interview question..
Initially there are n white balls. Each day you are allowed to take a ball. If the ball in hand is white, replace it by red ball. If it is red in color, put that ball into bag without doing anything. The question is to find the probability to have k red balls after d days.Give the general so... |
I'm trying to use an inverse hyperbolic sine transformation to reduce the effect of outliers in my target variable. Unfortunately, I don't appear to have access to the basic papers on it. I've found the formulation but am not sure how to estimate the theta parameter for it. Does anyone know?
Thanks
|
Then I fit linear models to the plot(n_clust, error) aiming to identify the best combination of I'm trying to perform a k-means cluster on my data (matrix with 2000 cases and 10 variables). I don't know how many clusters should I choose. To solve this problem, I adopted a strategy in which different values of K are set... |
I've been reading some materials on Spatial data analysis, and I've a good background in GLMs. Right now I'm looking to find an example in spatial generalized linear models, but so far I've not found any. I'm aware of some packages in R such as GeoR. etc. but couldn't find a concrete example that includes codes, data, ... |
This is a homework question, so I am looking for help in getting the right idea so that I can execute the rest of the work on my own.
I have some data regarding military veteran status and log-earnings. One of the questions says the following:
Estimate the returns to veteran status (an indicator variable, 0-not vetera... |
I am looking for an introductory book that helps building some skills in working with multivariate distributions.
For example, I want to be able to work with multivariate normal easily, something between an introductory stats course that talks about distributions and a serious robotics course that talks about Kalman fi... |
I'm looking for clarification: Do we have to run correlation analysis before carrying out principal component analysis (PCA), or is this implicitly subsumed under PCA framework?
I am on my way to write a research plan:
Isolate predictors with high collinear relationship to the process.
Run PCA to convert correlated p... |
I'm trying to model some time series data, and I've been reading about tapped delay line and sliding window to transform the input data.
In my understanding a sliding window with windows size 1 shifts the inputs by one at each time step and feeds them back to a feed forward neural network.
target| input
2| 1 0
... |
Possible Duplicate:
How is the minimum of a set of random variables distributed?
I have two RVs from the same distribution (exponential distribution with parameter λ). How do I calculate E(min|min>x)? I know how to get E(X|X>x) but I specifically need X to be the smallest of the two RVs.
|
Say I have a binary treatment, X, and I'm interested in its (local average treatment) effect on a binary outcome variable, Y. I find (binary) instrument T that directly affects X but not Y.
How do I estimate this? I get that linear models like TSLS might not be ideal, but Angrist and Pischke's "Mostly Harmless Econom... |
Suppose that I have a nested logit model. I can estimate the probability of making a particular choice for each decision maker. Now, I want to remove one or more of the choices (though each nest keeps at least one option). How can I estimate/simulate the new choice probabilities?
As a simple example, I might estimate a... |
After reading How Not To Sort By Average Rating which deals with confidence interval for a Bernoulli parameter how would you extend it to more than two levels?
For example: Items are scored between 1 and 5 (1 is worst 5 is best). What is the best way to adjust the average score per item in order to take into account th... |
I am having a conceptual hard time understanding where this formula came from. It does not seem to make any sense to me. Could someone shed some light on this:
The natural estimator of $p$ is $\hat p = \frac{X}{n}$, the same fraction
of success. Since $\hat p$ is just $X$ multiplied by a constant, $\hat p$ has an ap... |
When evaluating an estimator in a frequentist setting, using MSE and let say to compute the Bias of the estimator we compute the expectation of this estimator, are we supposing that the estimator has a probability distribution? doesn't this contradict the frequentist argument that a parameter is not a random variable? ... |
I am undertaking a study which has the following aims:
The main aim of the current study is to investigate the effects of food messages about the healthiness of foods on actual food intake.
Additionally, a secondary aim is to discover the extent to which impulsivity/sensation seeking, taste preference and BMI may mod... |
Here are some simulated data:
library(mvtnorm)
I <- 3 # positions (fixed factor)
J <- 4 # tubes (random factor)
K <- 4 # repeats
n <- I*J*K
set.seed(123)
tube <- rep(1:J, each=I)
position <- rep(LETTERS[1:I], times=J)
Mu_i <- 3*(1:I)
Mu_ij <- c(t(rmvnorm(J, mean=Mu_i)) )
t... |
Does vector autoregression (VAR) model require data to be of normal distribution? What are the pitfalls if the residuals are not of normal distribution?
|
As I understand it, the definition of the hazard ratio is the ratio of two hazard rates. Often the exp(coef) from a Cox model is also used as an estimate of the hazard ratio. These methods give two different, although similar, results. Are there circumstances in which it's appropriate to use one method vs. the other?
|
I know that bookmakers adjust their odds in order to maximize the gain, forecasting the probabilities of the volume of money placed in every outcome.
How do bookmakers select their opening odds?
|
I have a few related questions regarding the convergence of continuous-state Markov chains.
The theorems that I found claim that Markov chains converge in total variation if they are $\phi$-irreducible and aperiodic (e.g. http://arxiv.org/pdf/math/0404033.pdf, Theorem 4). I am confused by the fact that the way this res... |
In a set of lecture notes that I stumbled upon online, the author discusses a nonlinear regression model, which is linear in some parameters, like this
$$
y = \theta_1 + \theta_2\exp \left( {\theta_3x} \right) + \varepsilon
$$
and suggests to first perform a nonlinear regression to estimate $\theta_3$, and then use O... |
I am proposing a survey for my research proposal in speech therapy. There is a set of guidelines that speech therapists are supposed to follow, so that all questions are conceptually related - so that I can used a composite score if I understood that right.
My research question is Are speech therapists influenced by p... |
I'm not a statistician, but I'm interested in how far I can push myself with my basic algebra skills, armed with a C# development background and Excel.
Suppose I have several lotteries, each with different payouts, and odds, what is the right way to go about comparing and ranking the various games?
What would a graph o... |
I have designed a rather long (250 Qn) survey designed to uncover user clusters. The questions are such that the pattern of answering should elicit user clusters, but I am having trouble uncovering these with my analyses to date.
For example, a typical Qn might be: 'Are you more of a dog or cat person?' Or, 'Chocolate ... |
I'm just reading about the arcsine rule for the first time in the context of coin flipping, i.e., that one player is very likely to lead a large percentage of the time in a finite number of trials.
Question: Is whether there is a generalized version of this for biased coin?
I tried finding something via a search engine... |
I'm trying to mine that Stack Exchange data dump to find out whether there is a cluster of users that may be positively or negatively affected by the number of badges they've been awarded. The theory I'm working on is that for some people who were motivated by badges, that they eventually lose their appeal and they sto... |
I have carried out a study in which I have gathered 3 sentences per participant. These sentences were then classified in 2 ways. I want to test if there are significant interactions between the classifications and find out the effect size. I have done a chi square test for independence and calculated Cramer's $V$ (on t... |
I am a web developer and novice statistician.
My data looks something like this
Subject Week x1 x2 x3 x4 x5 y1
A 1 .5 .6 .7 .8 .7 10
B 1 .3 .6 .2 .1 .3 8
C 1 .3 .1 .2 .3 .2 6
A 2 .1 .9 1.5 .8 .7 5
B 2 .3 .6 .3 .1 .3 2
D ... |
I have a data set with 925 members that using Easyfit, I've determined is best fit using a Frechet distribution. Now, I'm trying to replicate this functionality in R to determine the optimum fit parameters using the VGAM package. Using this code:
vglm(V1 ~1, frechet2(location = 0), data, trace = FALSE)
I get the follo... |
I was recently looking at some standard error calculations using the following:
the formula for the covariance matrix in ordinary least squares (OLS)
the "robust" formula for the heteroskedasticity-consistent covariance matrix
the "modified-robust" formula (also called 'White' for its discoverer) for a bias-corrected ... |
In the year 2000, Judea Pearl published Causality. What controversies surround this work? What are its major criticisms?
|
Thank you in advance.
I am trying to build a model to predict the possibility of ordinal accident levels in a nuclear station if an accident happens. The accidents include four levels: Site_Area_Emergency, Alert, Unusual Event and Non_Emergency (In order of from Strongest to Weakest, Non Emergency is the weakest). I ha... |
In SAS enterprise miner we have the optimal binning feature which allows you to transform continuous variables into an ordered set of bins. The binning, as I read from one of their docs, is done so that the log odds of the predicted categorical variable (good/bad) is monotonically increasing or decreasing.
Can we use... |
I've got a method that produces clusters of elements and singletons. The singletons usually comprise about half of the initial element set, and there usually is a single biggest cluster of a several million elements, followed by a second cluster of a few hundred thousand elements, then the rest of the clusters with tho... |
I know this is probably a basic question... But I don't seem to find the
answer.
I'm fitting a GLM with a Poisson family, and then tried to get a
look at the predictions, however the offset does seem to be taken into
consideration:
model_glm=glm(cases~rhs(data$year,2003)+lhs(data$year,2003),
offset=(log(population)), d... |
It seems that through various related questions here, there is consensus that the "95%" part of what we call a "95% confidence interval" refers to the fact that if we were to exactly replicate our sampling and CI-computation procedures many times, 95% of thusly computed CIs would contain the population mean. It also s... |
I have the data with me however I don't have any idea as to how to analyze the variables. Can anybody help me? The variables/questions are as listed:
1. Gender
2. Age
3. Education Level
4. Occupation
5. Household monthly income (in PHP $)
6. Daily usage of the Internet
7. Have you ever used the internet for purc... |
The $r$-th moment of a random variable $X$ is finite if
$$
\mathbb E(|X^r|)< \infty
$$
I am trying to show that for any positive integer $s<r$, then the
$s$-th moment $\mathbb E[|X^s|]$ is also finite.
|
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