instruction stringlengths 9 38.7k |
|---|
I am interested in looking for periodicities in a several day long recording of electrical activity. The traces present a very steady baseline over which, from time to time, some short events (300-500 ms) appear (hence the sparse in the title, although I am not sure it is the right term to use).
Now, the nature of the ... |
First set: 12, 23, 24, 14, 29, 30, 31, 16.
Second set: 12, 22, 24, 14, 30, 30, 31, 16.
These data are obtained using a software (first set) and visual observation (second set) of the same process. I do not know if it matters it is expressed in minutes per 2 hours interval.
Thanks.
|
Suppose I have $N$ independent random variables $X_n$. I draw a sample of predetermined size $K_n$ from each of them. Denote the average of each sample $\bar{\hat{X}}_n$, and the total number of observations $M = \sum_{n=1}^{N} K_n$.
Next, I use all the $M$ sample observations $\hat{X}_{n,k}$, with no regard as to whic... |
I am trying to determine which room a person is in based on WiFi measurements. I currently have WiFi measurements for 3 rooms. The measurement consists of 100 WiFi scans collected from different locations inside each room. Each scan shows the number of WiFi APs visible at at some location inside the room. The number of... |
I have built a good model of time-to-stroke under cox ph assumptions using a predictor of stroke risk (Framingham risk score). It incorporates a score according to Age, Gender, controlled / uncontrolled bp, cardiovascular risk factors and can be seen here :
http://www.framinghamheartstudy.org/risk/index.html
I have hy... |
I am trying to find out answer for this simple question. I have data (list of numbers). I have 20000 numbers. smallest number is 100 and largest is 15000. I want to interpret this data, how it is distributed or any other suggestions, that how can I play with this data and do different things?
The thing is I have to gi... |
I have a training data set with both numerical and categorical variables, and one class variable. I want to build a classification model (e.g.,SVM), and for this goal I need to transform all variables into convenient format. I m confused about my categorical variables. Let me give you an example about one of them.
The ... |
I would like to know the distribution of z as the euclidean distance between 2 points which are not centred in the origin. If I assume 2 points in the 2D plane $A = (X_a,Y_a)$ and $B = (X_b,Y_b)$, where the $X_a \sim \mathcal N(\mu_a,s^2)$, $X_b\sim\mathcal N(\mu_b,s^2)$, $Y_a\sim\mathcal N(\nu_a,s^2)$, $Y_b\sim\mathca... |
Kendall's tau is an association measure between two random variables, say $X$ and $Y$.
If $X$ and $Y$ are independent, then $\tau = 0$. However, $\tau = 0$ does not imply independence because kendall's tau only captures monotonic association. Is there some conditions under which one has equivalence?
Edit to account fo... |
I am specifically confused as to the meanings of the shaping and scaling parameters of the gamma distribution and how they are used in a real context. Once I find the correct parameters, I have the equations to find everything else I need.
The word problem that I am looking at is:
Audrey, an astronomer is searching fo... |
I am attempting to group, for example, strings about programming with other strings about programming, strings about physics with other strings about physics, etc., for a wide range of topics. Despite the glaring theoretical linguistic aspect of the problem, I am looking to actually do this using programming/software.
... |
I am using the glmer() function from the lme4 package to run a GLMM using the poisson distribution. In all the examples that I see, the random effects part of the output has a residual part that has been estimated from the data (surrounded by 2 asterisks on either side in the example below). This information can then... |
I've got a database showing signatures added to a petition, with each signature linked to a location (city, state), a date, and a sequence in the date (e.g. the seventh signature on 3/26 came from Rochester, NY).
I'd like to detect geographic patterns in the data - e.g. when one signature from Rochester leads to furthe... |
I'm simulating a multivariate dataset using a modified form of the mvrnorm() function (from the MASS package in R).
The problem is that I'm getting some negative values after the eigenvalue transformation (I assume) because I have many negative correlations and a number of small means.
Is there a special way to deal wi... |
I have the following linear model based on multivariate timeseries:
lm(formula = Y ~ X1 + X2 + X3 + X4 + X5 + X6 + X7, data = model.data, na.action = na.omit)
Residuals:
Min 1Q Median 3Q Max
-0.0030132 -0.0002101 0.0000004 0.0002101 0.0035819
Coefficients:
Estimate... |
I have a model which I built with a number of factors as fixed effect variables. Up to now they all had two values e.g. high tide/low tide and so when I ran the summary it would show one variance for the variable (but it had a 2 next to those coded as an as.factor). After suddenly running a fixed effect with four IDs (... |
Using Stata 11.2, I would like to develop 2 analytic models that could be implemented by school administrators to flag students for intervention. I'm wondering if it would be possible to develop these models based on historical cross-sectional data consisting of 650,000 unique observations (11th grade students); it wa... |
I would like to calculate the power of a Chi-Square test for goodness-of-fit as a function of sample size for a specified alpha-value (say 0.01). Specifically, I am referring to power as the probability that the test will correctly reject the null hypothesis. In most places I look, I can find only vague references th... |
I have a dataset with two overlapping classes, seven points in each class, points are in two-dimensional space. In R, and I'm running svm from the e1071 package to build a separating hyperplane for these classes. I'm using the following command:
svm(x, y, scale = FALSE, type = 'C-classification', kernel = 'linear', cos... |
Let's say that I have an object of class glm (corresponding to a logistic regression model) and I'd like to turn the predicted probabilities given by predict.glm using the argument type="response" into binary responses, i.e. $Y=1$ or $Y=0$. What's the quickest & most canonical way to do this in R?
While, again, I'm aw... |
It is possible to calculate the c-index for time dependent outcomes (such as disease) using the survivalROC package in R. My question is : is it possible to produce a p-value for the c-index that is calculated (at a specific point in time)?
If I were to use a standard ROC I understand that I can use Wilcoxon test to c... |
I have developed a recent interest in propensity scores. I have been using the SPSS tool created by Dr. F. Thoemmes to calculate propensity scores using bivariate "treatment" variables (e.g., depression) and several covariates (e.g., age, sex, persons in household). I am then given a resulting propensity score, but am ... |
Is there like a diagnostic checking (like those in the time series) done for logistic regression and complementary loglog model?
|
I have a Bayesian model here in R/WinBUGS. This data "pumps" has two columns, time and fail. Each observation is a pump and fail[1] tells how many failures there were in time[1]. I want to know how I can write this same model in SAS using Proc MCMC. Thank you!
pump <- function() {
for(i in 1:10){
fail[i] ~ ... |
The impression that I got, based on several papers, books and articles that I've read, is that the recommended way of fitting a probability distribution on a set of data is by using maximum likelihood estimation (MLE). However, as a physicist, a more intuitive way is to just fit the pdf of the model to the empirical pd... |
For a Bernoulli distribution with parameter p, the number of trials with a 50% probability of at least one success is about (1/p) * ln(2). But the expected value of the corresponding geometric distribution is 1/p. Intuitively I would expect them to be the same (1/p). What am I missing?
|
EDIT
I am playing with pattern recognition techniques and just to get a grip of it for simplicity I have tried to develop a classifier which categorizes strings into 3 classes based on the probabilistic frequency count under labels A,B,C; each label indicating the dominance of the letters which means if a string of fix... |
Two related questions from me. I have a data frame which contains numbers of patients in one column (range 10 - 17 patients) and 0s and 1s showing whether an incident happened that day. I'm using a binomial model to regress probability of incident on number of patients. However, I would like to adjust for the fact that... |
It seems to me that in literature these terms are used synonymously.
Does spatial autocorrelation strictly refer to linear dependence, or does spatial autocorrelation refer to the set of measures of spatial dependence (moran's i,...)?
Do you know of any precise definition of both terms?
Thank you very much
|
Image below is a Matlab plot from 3-layer perceptron learning with 2 hidden nodes in both hidden layers. Are there simple technique or simple coding to remove or detect these fluctuations during training?
What I've tried only is to reduce step size but I had to compensate that with increasing number of iterations.
Plea... |
Given a set of experimental data f={fk} for k=1,2,...,N, how can I find the best pdf which approximate the set fk? In the case of a gaussian distribution, applying the maximum likelihood criteria, it's easy to find the couple (μ,σ), but if I don't know anything about the distribution of the data, is the maximum likelih... |
Does anyone know of a large data set (upwards of $10^7$ rows, but I'll take $10^5$ as well) that would be appropriate for testing kernel logistic regression? Continuous variables, 2 to 50 independent variables? Would prefer business-like data as opposed to scientific (weather, chemical, bio ...).
|
Let's say I have a list of users who have specified the country they reside in by typing in something. I want to find the total number of users who came from the US, the UK, and everywhere else. But, since users typed in their country manually my data looks like this:
USER COUNTRY
1 USA
2 United States
3 ... |
Ok, I have searched and searched and just have no clue where to start. First, what I would like to do is produce a QQ-plot (or even a readable residual plot) to look at the fit of my model. I guess I just don't understand how the parameters that go into qnbinom() are obtained from the output of MASS::glm.nb(). I am ... |
I am assessing the acceptability of a sentence in a within-subjects design with two crossed factors (type of sentence, missing word). After reading each sentence, the participants answer a simple yes/no question which is my dependent variable.
Because a dichotomous variable is not normally distributed I am guessing I c... |
I've run a chi-square test of independence on a two-way table with two categories on the rows and four categories on the columns. My $p$-value is below my chosen $\alpha$, so I may conclude that the rows and columns of this two-way table are dependent. I'm having trouble characterizing the dependence among the rows and... |
I have four datasets: D1, D2, D3 and D4. Each dataset contains elements (different sample size in each dataset) that can be described by 100 categories (1 represents that the element belongs to that category and 0 represents otherwise). So for example,
D1
Element Category 1 Category 2 Category 3 ...... |
I have been doing some research on constrained models and have recently read the paper:
Gunn and Dunson (2005) "A Transformation Approach for Incorporating
Monotone or Unimodel Constraints", Biostatistics, 6, 434-449
In this paper they advocate fitting an unconstrained hierarchical model, and then applying the cons... |
Let's say I have a ton of credit card usage data and have also some means to predict if a given transaction is fraudulent. Now I want to know what kind of criminal entities are behind these frauds. Maybe some are big international/domestic crime organizations, some are small groups and some are individuals etc.
I'd ass... |
The Mega Millions is over $500 million today. I remember reading a JSTOR paper about some numbers that are most unlikely to be chosen. For example lots of people choose 7 because it's their lucky number, and I want the opposite of that. However my JSTOR membership has ran out. Which numbers are least likely to be chose... |
Lets assume one has 2 datasets: with different number of rows (samples) and columns (features). Each of these 2 datasets have a column as a binary response variable. Lets say healthy or not.
What sort of statistical methods can be used to help us for better feature selection results, or better performance in classifica... |
I want to know how to to input a self-defined distance in R, in hierarchical clustering analysis. R implements only some default distance metrics, for example "Euclidean", "Manhattan" etc. Suppose I want to input a self-defined distance '1-cos(x-y)'. Then what should I do?
Writing a function is obviously a solution. Bu... |
I am confused on why a simple trend process is not stationary. Consider the following process:
$Y_t = a + bt + \epsilon_t$
The variance is clearly constant. However, the mean $bt$ is dependent on $t$. When shifted in time, the mean only depends on the time interval and is independent of history. For example, $Y_{0,t}$ ... |
Lets say you have a class $C$ of binary strings $s$, and each string corresponds to one of $n$ categories. How do you quantify the complexity of the relationship between the sequence of bits in $s$ and the categorization of $s$.
For example, Imagine your strings are 6 bits long, $n=2$, and the first bit is the only one... |
I'm in the process of analysing different PHP frameworks and part of this involves testing the load times. For this, I've programmed various usage scenario's. I'm however quite unsure on how to proceed from this.
I'm using Apache Benchmark to simulate the number of requests and the number of concurrent requests.
When ... |
Suppose I have a predictive model that produces, for each instance, a probability for each class. Now I recognize that there are many ways to evaluate such a model if I want to use those probabilities for classification (precision, recall, etc.). I also recognize that an ROC curve and the area under it can be used to... |
I have several dependant variables that are non normal in distribution: Kolmogorov-Smirnov test is significant, skewness ranges up to 8 for some variable, and kurtosis is generally about 2 but in a couple of cases raises to 12! It is a repeated-measures (RM) ANOVA model for the normally distributed variables.
A coupl... |
So I apologize ahead of time if this isn't the correct venue for this question. I've been having a debate with a friend of mine for a few days now about what the best way to run a bracket is for a tournament I am having for a video game. No need to know anything about the video game at all, purely that there is not a s... |
My first question here, hope to be relevant to the community. Im into CS course and a total rookie on statistics, so let me know if more detail is needed and I will edit the post.
I have a problem now that we want to compare sample groups and wanted to come up with a function out of it, so we moved from ANOVA to ANCOVA... |
I am a PhD student and am conducting a literature review on musculoskeletal physiotherapy and am struggling to get guidance on this subject as most health researchers conduct meta-analyses of intervention effects/ effectiveness and not of correlations.
I am looking at the predictors of attendance and adherence to treat... |
I'd like to estimate the unique effects for each variable in a linear model,
however I am unsure if I calculating these correctly.
I am using a model estimated using each of the variables in my data plus a
binary interaction with each variable, e.g. y ~ x + x:z where x is a vector and
z is two factors which is prese... |
I need to chart a number of indicators to evaluate emergency response times for a fire department. In our case, most values should be around 2 minutes, but the range can be between 0 and 10 minutes.
I've been working with bar charts (and Few's bullet charts), however, since bar charts work on comparing lengths, an... |
Consider $n$ fixed subsets of a finite universe $U$: $A,B,C,D,\ldots$
Then let $Coll$ be the collection of sets we get from the closure of the set $\{U,A,B,C,D, \ldots\}$ under the operations $\cup,\cap$ and set-theoretic difference.
(As an aside, to help picture Coll, note that $|Coll|≤ 2^{2^n}$ Imagine an n-ary Ven... |
Is there a term for using the best and worst results of a neural network classifier as labelled input for another neural network? Or isn't this approach valid at all?
E.g. I train a neural network and then I classify unlabeled samples with this neural network. The outputs I use a labelled training for a new neural netw... |
I have random samples $X_1, X_2, X_3$ from $bernoulli(p)$. The critical region for testing $H_0 : p \leq 1/2$ vs $H_0 : p > 1/2$ is $C =\{(x_1,x_2,x_3): \sum_{i=1}^3 x_i \geq 2\}$.
Now I want to find the size of this test and the power function of the test.
|
There is a question with similar intent on programmers.SE. That question has some quite good answers, but the general theme seems to be that without self study, you get no-where.
Obviously there are some major difference between programming and statistics - with programming, you're really just learning some basic logi... |
I have a binary classification problem.
My inputs consist of a time-series of values plus some binary values.
For real-valued inputs I would usually use a neural network, while for binary-values inputs I would use either a neural network with a step function or some other method fit for binary inputs (like a maximum e... |
I have a function which simulates the outcome of a particular card game, and returns a value denoting the outcome of the game. I want a concise syntax for sampling multiple plays of the game, and getting a vector containing the outcomes. This is what I want to be able to write:
sample(cardgame(params), iterations, repl... |
I looked at whether participants recycled after being subjected to a given message. There were three groups: a Control group, group A, and group B.
Since my dependent measure was dichotomous (recycling vs. using the waste bin), I performed a logistic regression in SPSS. However, SPSS only let me compare individual grou... |
Assume I have a process that I assume to be Poisson, meaning that the waiting time between events is exponentially distributed. As a concrete example, assume I want to estimate the waiting time to a car accident at an intersection. These accidents happen infrequently, so the data I have must be used efficiently. It ... |
I have a picture from a very old archive. It is a list of tuples (var, percentage). The problem is that I have only the 13 top values, ordered on percentage.
In python I decided to write it as a dictionary.
myolddictionary = {'var1': 0.64,
'var2': 0.63,
'var3': 0.40,
'var4': 0.38,
'var5': 0.36,
'var6': 0.34,
'var7': 0.... |
Before performing the task of text mining, we need to select the features for characterizing each given document. Are there any systematic guidance on choosing the document features? How does the length of the document affect the feature selection process for the documents?
|
Is there a belief propagation algorithm for exact inference on a MRF with complex clique structures (i.e. ones involving more than 2 neighbours)?
For MRF's with cliques that only involve pairwise interaction, you could just search out far enough and cluster to form an acyclic graph and run the usual BP. With more comp... |
Low-discrepancy sequences in a real space ($[0,1]^n$) seem like a really excellent tool for evenly sampling a sample space. As far as I can tell, they generalise well to any real space, if you use an appropriate map (eg. $[0,1]\to[a,b]$ linear map).
Do such sequences generalise to discrete spaces? eg. if I have a space... |
Following zzk's question on his problem with negative simulations, I am wondering what are the parametrized families of distributions on the positive k-dimensional quadrant, $\mathbb{R}_+^k$ for which the covariance matrix $\Sigma$ can be set.
As discussed with zzk, starting from a distribution on $\mathbb{R}_+^k$ and... |
I am currently working on a project dealing with time series data but I have little experience with time series analysis so I was hoping to get some direction on what kind of exploratory data analysis techniques and models I should be looking at, so that I can read up on my own.
I have two weekly time series (movie sal... |
I am looking into time series data compression at the moment.
The idea is to fit a curve on a time series of n points so that the maximum deviation of any of the points is not greater than a given threshold. In other words, none of the values that the curve takes at the points where the time series is defined should be... |
I am fairly new to statistics.
Currently I am into (histograms) medians, arithmetic mean and all the general basics.
And I came across the fact/rule that the arithmetic mean is (always) larger than the median if the distribution is skewed to the right.
Why is that?
(I would appreciate a rather simple or easily understa... |
I have the joint distribution of the bayesian network defined as
$P(CERFD)=P(C)\times P(R)\times P(E|CR) \times P(F|E) \times P(D|F)$
and I am trying to calculate $P(D=d|C=c)$, below are my workings and I am stuck at the last step:
$P(D=d|C=c)= \frac{P(D=d,C=c)}{P(C=c)} $
$=\frac{\sum_{ERF}P(C=c)\times P(R)\times P(E|... |
I need to use ANCOVA to analyse effect of executive functions (EF-covariate) on scores collected during a test. I want to compare this effect between a control and schizophrenics group (variable diagnoza).
I conducted an analysis of covariance and I have some questions.
Here is SPSS output for my ANCOVA model:
Is it ... |
I am analyzing data from an experiment in which participants had to respond to Yes/No-questions of two types as quickly as possible. Hence, there are two dependent variables: response time and correctness of the response. There are 80 responses for every participant in each of the conditions. My hypothesis is that one ... |
Suppose I want to generate a $n \times n$ orthogonal matrix $H$ (that is, $H^T H=I$) but with the property that $1-e < (tr H)/n < 1+e$ for some pre-specified tolerance $e$. How can I do this? Ideally I would want them to have the Haar distribution (conditional on the trace restriction) but I would settle for any meth... |
Are there any R packages that share the similar functionalities of NLTK toolkit?
|
Inspired by this question, I'm wondering whether any work has been done on topic models for large collections of extremely short texts. My intuition is that Twitter should be a natural inspiration for such models. However, from some limited experimentation, it looks like standard topic models (LDA, etc) perform quite p... |
Is there a simple way to determine (other than by simulation) the expected standard deviation of a sample, when sampling from a population with known distribution, for example a normal distribution with mean 25 and standard deviation 5, but the samples are included/excluded if they fall within certain limits ? In parti... |
I'm looking for the paper:
Streitberg and Rohmel (1986) Exact calculations for permutation and rank tests: an introduction to some recently published algorithms. Statist. Soft.Newsletter, 12, 10-17.
Google Scholar shows a citation, but not a link, and says that it's cited by 60 other papers. It appears that the Statist... |
I am trying to train an Artificial Neural Network for classification. In the input layers, I have 402 neurons; the first 400 are binary, and the last two are floating points in the range -1 to 1. In the hidden layer I have 400 neurons, and in the output layer I have a single node which I want to represent values betwee... |
I have a sample of data generated in R by rnorm(50,0,1), so the data obviously takes on a normal distribution. However, R doesn't "know" this distributional information about the data.
Is there a method in R that can estimate what kind of distribution my sample comes from? If not, I will use the shapiro.test function ... |
In a configuration model where each node has a degree 2. What is probability that a node belongs to a component of size n.
|
I'd like to find out if there is a statistical test that I could use to determine if a mean difference is significantly greater than another mean difference.
To determine if one mean is different from another mean, I would use a t-test, but that would not apply here because there are not actual distributions; instead... |
I need to predict the outcomes of a time-series variable $Y$ based on two time-series predictors $X1$ and $X2$. For simplicity I will only illustrate $X1$ in the rest of this question.
The correlation between the predictors and $Y$ at lag 0 is relatively high as illustrated by the cross-correlation function. However th... |
If we build a classifier based on a very small number of instances (say, fewer than 300) and the number of features we are using is very large (say, larger than 100k features). If we decide to introduce a feature selection step before building the classifier, is there a rule of thumb on how many features we should choo... |
I performed the Kruskal-Wallis one-way ANOVA by ranks on five groups of data using Dataplot software. The software corrects for ties and uses Conover's procedure to do pairwise multiple comparisons.
The result of the test is $H=5.62$ and $p=.229$ so the results are not significant ($p$ is not less than $.05$). Howeve... |
I would like to generate data points with given regression coefficients, where some of the variables may be discrete and some continuous, and I am performing both "direct" and "reverse" regressions.
For example, I would like to generate data points consisting of triples $(x,y,z)$ where $x$ is either 0 or 1 and $y$ and ... |
My question is like this.
The regression specification is:
$y=\delta_{1}D_{1}+\delta_{2}D_{2}+\delta_{3}D_{3}+\beta_{1}x_{1}+\beta_{2}x_{2}+\beta_{3}x_{3}+\epsilon$
where $D_{i}$ denotes dummy for each one of three categories, $x_{i}$ interaction between $D_{i}$ and independent variable $x$.
I want to test $b_{1}=b_... |
I have binomial frequency data for an allele associated with populations living in mountainous. These mountains run north to south where sites are nearly fixed for this allele and lowland sites to the east that lack the allele. At the south end of the mountains is a hybrid zone. Despite the mountains continuing south t... |
The regression specification is:
$y=\delta_{1}D_{1}+\delta_{2}D_{2}+\delta_{3}D_{3}+\beta_{1}D_{1} \cdot X+ \beta_{2}D_{2} \cdot X+\beta_{3}D_{3} \cdot X+\epsilon$
where $D_{i}$ denotes dummy for each one of three groups, $D_{i} \cdot X$ interaction between $D_{i}$ and independent variable $X$.
Each group has different... |
Say I have a set of data which I know comes from a Binomial distribution (generated using the rbinom function in R).
Is there any way to use the data to work backwards and work out the p and n parameters of the Binomial distribution from which it came?
EDIT: I realise that there are infinite combinations: n = 100 and p... |
This question might be very basic, but somehow I don't understand this point.
Suppose initially I used a univariate regression equation such as
GDP=a+b*Income
I'll get some coefficient values (say 0.5). Now, I'm using the same structure of the regression model, but added another independent variable. So, the new equ... |
I am looking for the references on non-linear regression analysis. I am mostly interested in introductory textbooks focusing on theory, but covering some applications as well.
|
I have a dataset with 9 continuous independent variables. I'm trying to select amongst these variables to fit a model to a single percentage (dependent) variable, Score. Unfortunately, I know there will be serious collinearity between several of the variables.
I've tried using the stepAIC() function in R for variable s... |
I have a database that contains daily stock returns of more than a thousand stocks for many decades. I would like to achieve the following goals:
Construct a time-varying measure of co-movement (or common component) of stock returns.
Compare the evolution of this measure over time, and later relate it to other variabl... |
I have problem with homogeneity of regression slopes in ANCOVA. I have two species of snakes and I want to compare their tail lengths (dependent variable), that are dependent on body length (in ANCOVA used as covariate). Other ANCOVA assumptions are met, but there exist significant interaction between species*bodylengt... |
In a sample of 250 cardiac patients who have had a myocardial infarction and just left hospital, I asked them how important it was to them to know several issues, such as "How important is it for you to know when to return to work, or when to revisit the hospital" etc. Answers were provided ranging from "not important ... |
Is an implementation of a density function for a logit-normal distribution available in R?
I have not found one in a package or in the CRAN task view of probability distributions.
This is for a MLE fitting of a function to data.
|
In ecology, we often use the logistic growth equation:
$$ N_t = \frac{ K N_0 e^{rt} }{K + N_0 e^{rt-1}} $$
or
$$ N_t = \frac{ K N_0}{N_0 + (K -N_0)e^{-rt}} $$
where $K$ is the carrying capacity (maximum density reached), $N_0$ is the initial density, $r$ is the growth rate, $t$ is time since initial.
The value of $N_... |
I have a couple questions about Cox survival regression:
1) Is it true that the hazard function h(t) is not available (even WITHOUT time dependent covariates)- and if not, is it because the baseline hazard is not defined (only the cumulative hazard is and you cant go from the cumulative hazard to the hazard)?
2) When y... |
I've been looking for the internet explanation about the hidden Markov model (HMM) and its implementation but I think there's not quite good explanation. Does anyone know and guide me through this like tutorial and its implementation. There will be feedback and not do this as charity.
So I hope there will be someone in... |
Books to Learn Statistics using R
What exactly is the book I'm looking for.
What I am looking for is a book that teaches you statistics while using R to give you hands-on experience and thus end up helping you learn R together. I've seen on amazon many books that attempts to do that, but not with R. Examples are Minita... |
I'm in the process of calculating inventory levels for a bunch of SKUs and I'm wondering if you all-mighty statisticians had any card up your sleeves that I could borrow.
Here's the deal: service levels are inevitably going to be affected by the amount of material I decide to put in stock. The more I stockpile, the hig... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.