0
votes
1answer
59 views
+50

hurdle model with negative binomial distribution of counts - error message and model selection

I'm working with over-dispersed count data, which is zero inflated (~2/3 zeros). I've fit a hurdle model using hurdle from ...
3
votes
1answer
95 views
+50

Measuring length of intervention effect

I ran a study in which participants were randomized to either a control or an intervention, with outcomes in the form of time-to-event data. While overall time-to-event is shorter in the intervention ...
0
votes
1answer
106 views
+50

Confidence interval for observational study

I recorded hand hygiene type for 500 nurses following 500 episodes of care. I now have a probability for each type of hygiene method: Alcohol gel, Soap, Gloves, None. But how do I calculate a ...
2
votes
2answers
66 views
+50

Naive bayes with duplicated data

In the training set for naive bayes, there are some duplicate samples. Should we train the naive bayes with duplicate samples, or should we eliminate all the duplicates and then train the naive bayes. ...
1
vote
0answers
49 views
+50

Comparison of frequency rates

Patients with chronic schizophrenia will take some antipsychotic drug during some period of time. The frequency of schizophrenia for each patient will be recorded before and after that period. I ...
3
votes
0answers
42 views
+50

Missing values with Community structure in networks?

Is there a way to predict Missing values with Community structure in networks? I have a data set with a couple dozen variables, such as age, level of education, self-assessed (via a Likert scale) ...
1
vote
1answer
59 views
+100

Local polynomial regression: Why does the variance increase monotonically in the degree?

How can I show that the variance of local polynomial regression is increasing with the degree of the polynomial (Exercise 6.3 in Elements of Statistical Learning, second edition)? This question has ...
1
vote
2answers
81 views
+100

Inverted nonparametric rank test

I have two related samples, for which I want to prove they are not significantly different (normally you would test for the opposite, i.e. samples are significantly different). If I use Wilcoxon ...
3
votes
0answers
55 views
+50

Regression, Loss Function, Estimation Dilemma

I am trying to have an in depth understanding of predicting the value of a random variable given additional information. Suppose that $Y$ in $R$ and and $X$ in $R^n$. We would like to have a best ...
0
votes
0answers
30 views
+50

What does it mean to say that “a topic is a distribution on words”?

I was taking a machine learning course and they say the following two phrases that confuse me: each document is a distribution on topics. and each topic is a distribution on words. I was ...