Linked Questions

2 votes
0 answers
44 views

How to model zero-inflated mass data? [duplicate]

I am working with a data set of the mass of plastic found at various sites. At most sites, we found no plastic and so the data is zero-inflated (see histogram below). I want to model the data using ...
Eleanor Weideman's user avatar
14 votes
10 answers
12k views

Is a distribution that is normal, but highly skewed, considered Gaussian?

I have this question: What do you think the distribution of time spent per day on YouTube looks like? My answer is that it is probably normally distributed and highly left skewed. I expect there is ...
Cauder's user avatar
  • 337
45 votes
3 answers
15k views

Is a "hurdle model" really one model? Or just two separate, sequential models?

Consider a hurdle model predicting count data y from a normal predictor x: ...
Mark White's user avatar
  • 10.5k
11 votes
2 answers
9k views

How should I model a continuous dependent variable in the $[0, \infty]$ range?

I have a dependent variable that can range from 0 to infinity, with 0s actually being correct observations. I understand censoring and Tobit models only apply when the actual value of $Y$ is partially ...
Robert Kubrick's user avatar
4 votes
4 answers
2k views

Alternative to log when doing linear regression on multiplicative dataset with zeros

I'm doing work on a dataset that is approximately lognormally distributed, but with significant amounts of zeros (kinda like looking at forum post activity per subforum. For those who do post, the ...
Ingolifs's user avatar
  • 1,724
6 votes
1 answer
12k views

Linear Regression for a discrete count dependent variable?

I want to model the number of trips taken by households to investigate the effects of income, number of cars available, etc. on the number of trips. One potential issue is that the probability ...
J_D's user avatar
  • 61
4 votes
2 answers
6k views

Response variable: percentage and too many zeros (zero inflated Poisson?)

I am analysing the effect of density (categorical), gonad mass (continuous) and temperature (continuous) on the percentage of acini spawning in a gonad. My replicate unit is a scallop. As my response ...
Tania Mendo's user avatar
4 votes
1 answer
5k views

GLMM with poisson distribution for non-integer "count" data

Excuse me if this is duplicated. I've poked around this and other sites and have found some good info about glmm's and Poisson distributions, however my case seems a bit different. I am currently ...
Wendal Kane's user avatar
5 votes
2 answers
4k views

Justification for using a zero-inflated negative binomial regression

I'm trying to describe in words why I used a zero-inflated negative binomial regression instead of an negative binomial regression: To model my data I used a negative binomial regression. However, as ...
luciano's user avatar
  • 14.5k
2 votes
1 answer
3k views

Very skewed and zero-inflated continuous outcome variable

I am trying to predict a positive and continuous outcome by using the generalized linear model in R (glm function) and I am wondering what family could I use for the training data. Some of the ...
Dimitrios Torssøn's user avatar
2 votes
1 answer
2k views

Confused on how to interpret ZINB and Hurdle models

Below are a set of results from a zero-inflated (AIC = 64992.15; BIC = 65280.78) and hurdle model (AIC = 65141.73; BIC = 65430.36) for a dataset (>18000 obs) which describes the number of illicit ...
James R.'s user avatar
0 votes
1 answer
4k views

Dealing with zero-inflation if the data are not count data type

In the literature I found that for the count data with a lot of zeros so-called zero-inflated distributions (models) and so-called hurdle-at-zero distributions (models) could be used. The differences ...
Eco06's user avatar
  • 157
2 votes
1 answer
2k views

R: hurdle models with date as non-nested random effect

I have litte experience with GLMM's and I need to use Hurdle models for the first time, but I'm really confused about the random effect part. I have a dataframe with counts of flies caught in traps ...
Tingolfin's user avatar
  • 205
0 votes
1 answer
860 views

Regression where dependent variable not normally distributed - logistic regression, negative binomial model, poisson model?

I'm conducting a study about social media posting with pets. My dependent variable is pet posting frequency (total pet pictures/total pictures posted), and a significant number of participants did ...
sqlnewbie1979's user avatar
3 votes
1 answer
2k views

Implementing a hurdle/Zero-inflated Poisson model in R with right-censored count data

I'm trying to fit a hurdle/zero-inflated (I haven't decided yet) model on microbiological water quality data that is also right-censored: either the water sample is contaminated with bacteria or not, ...
Lily Atkins's user avatar

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