model

  1. G

    Cave Temperature Analysis, Real life management issues.

    Hi, I've taken math course's up to Calc III and Diff Eq, but never a statistics course. So I was hoping this forum could help me. I am working with 10+years of temperature data taken from several loggers throughout a cave system. The loggers record temperature every 30mins, which I have...
  2. B

    Model conception

    Hello! I have a basic stats question: I want to model a phenomenon, and estimate parameters. How many observations would I need, to be as accurate as possible? I think it might have something to do with the degrees of freedom, but I am not exactly sure how to use this information. From the...
  3. T

    HELP - citation model in R

    Hello everyone. I need help with the citation model as explained in This article "Bibliometric tools applied to analytical articles: the example of gene transfer‐related research" The model is expressed as C=KY+S C=cumulative number of citation Y=article life K=citation rate (number of...
  4. A

    Drift Diffusion Model

    Hello I have RT-Accuracy data. I want to estimate the parameters of a drift diffusion model (Ratcliff, 1978). I am assuming that: v(t)=v(t-1) + v + e(0,s). meaning that at each giving time evidance is accumulated from a normal distribution with expected value v and noise s. I am very very new...
  5. N

    I am too new for words

    Ok, I am quite new to statistical analysis and will be training myself. I am working in Quality Assurance at a nuclear site. Here is the premise: Many models of issue deficiencies us a "Bird's Triangle" model. Industrial Safety for example. In each tier of blocks the numbers change to indicate...
  6. C

    Hierarchical regression for a complex model

    So I am testing my own model but it is more complex than I have dealt with before. I know I need hierarchical regression, and I'm using SPSS (I have no choice in programme, sorry), but I can't find a tutorial close enough to what I'm doing to be sure it's right. I have one IV (3 categories...
  7. S

    Defining model - are my samples too small?

    Hello, I am attempting a valuation of a non-market good. This non-market good is made up of a number of component parts. I have conducted a meta-analysis of these valuations and am attempting to model these to establish which explanatory variables given about the good explain values given...
  8. C

    Suitable Model

    Hi all, I wonder if anyone could help me, i'm looking for an idea or two :) I work in the financial sector and we are looking into ways of predicting the behaviour of customers following changes to rates on some of our products. The current process involves looking at previous rate...
  9. Y

    Help with research model

    I am in need of a quick statistical advice for a study I planned, and I hope you can help me a bit with it. I'd really appreciate your expertise. Here's a link to the model: https://drive.google.com/file/d/0B_S37tP6GGAAZWU2ZkxuZk9NVVVDaUNYVzZyWlBjVmZLRmdV/view?usp=sharing The model looks...
  10. W

    Comparing self made models

    Hello! I have a quenstion about comparing models. Not models fitted by R itself, but user defined models. Ill explain through this example: Dataset: Tree Diameter Biomass Model1biomass Model2biomass 1 10 50 45 60 2 7 35 52...
  11. Lukan27

    Help on interpreting linear regression

    Help on interpreting linear regression estimates I'm currently working on a larger assignment, and I need some input how to interpret the results from my/a linear regression. I'm pretty sure I get it right, but as a precautionary measure some input would be lovely. I've websearched and...
  12. R

    Standard deviation and sample size

    Hi. I have no background on statistics, so please just go down to fundamental for me. But here are some basic questions about statistics and standard deviation .... Assuming study from 20 samples (please don't mind the sample size) found that, for example an average American play 3 +/- 2 hours...
  13. R

    Which regression model should I apply?

    Dear all, I want to do an empirical analysis on the risk-return characteristics of venture capital investments across industries applying a discrete binomial tree model. Therefore, I want to do a multiple regression. However, I am struggling with the decision which regression model I should...
  14. D

    Partial Least Square Regression_Interpretation of Result_VIP_Model Equation_urgentpls

    Hello! I would like to ask your help about the interpretation of my results. So I am doing an analysis about which among the environmental predictors (X variables) are the most influential in the coral cover dostribution (Y). I was advised to use partial least regression with the type of data...
  15. J

    AMOS - Confirmatory factor analysis - why the zero's on my error terms?

    Morning, I am trying to complete a confirmatory factor analysis in AMOS (255 subjects, 57 variables, 3 factors). I understand why AMOS automatically sets the regression weights of error terms to 1, however I am not sure what the zeros appearing above every error term are (a 0 with a small 1 to...
  16. P

    Model with discrete variables like step function

    I have some data and I want to use a model such as linear regression to describe the relationship between y and x. 2001 2002 2003 2004 2005 2006 2007 y: 0.1 0.4 0.2 0.5 0.8 0.9 0.2 x1: 0.4 0.4 0.4 0.4 0.5 0.5 0.5 x2: 0 0 0 0 0...
  17. J

    Help with linear regression model?

    I need to construct a linear regression model for the following information but i'm not entirely sure how to do it! S H L D Y 0 0 0 0 7.06 0 0 1 0 4.42 0 1 0 0 8.83 0 1 1 0 7.81 0 0 0 0 7.73 0 0 1 0 6.69 1 0 0 1 11.74 1 0 1 1 9.91 1 1 0 1 12.63 1 1 1 1 12.85 1 0 0 1 9.57 1 0 1 1...
  18. P

    number of variables for a model

    I am now trying to build a cox model: h(t, beta) = h0(t)exp(X*beta) I have selected some variables from the data, and for a category variable, if it contains N categories, I will set up N-1 dummy variables for it, if so, there are 26 variables in my model, is it too many for a model? But...
  19. B

    Advice on Regression Model Using PROC GLM in SAS

    Hi Everyone, thanks for your insight on this. I will try to explain my data set as well as possible. One of the models I am running on my data set includes have 2 continuous IV's predicting 1 continuous DV. However each of these IV's were derived multiple time under differing crossed...
  20. P

    cox model with time dependent covariate

    I am trying to fit a cox model: h(t, beta) = h0(t)exp(X*beta), while X = (x1, x2, ..., xN) but, for instance, x1 is binary with value of 0 or 1, but the hazard ratio of 1 and 0 is not proportional: t: 1 2 3 4 5 6 7 .... hazard ratio: 0.2 0.3...