1. B

    bayesian statistics

    I have a large amount of data, given totals for every hour over a year period for the following columns: # of Jams Jam event time in minutes # of Full occurances Full event time in minutes and Runtime, product flow (counts) I am trying to create a bayesian model using iPython and...
  2. C

    Ranking a Location using Linear Regression

    Hi, I am facing a strange problem with a software patented in the USA. It is a location evaluation software, which offers insights on determining the best location for starting-up a gas station / petrol station. While reading the patent thoroughly, I feel that the software operates based...
  3. S

    regression on age groups

    Dear All, I have the following question: Estimate a simple regression model of ‘libertarian-authoritarian’ attitude as a function of age groups and comment on the sign, significance and magnitude of the effects. I have one variable (and only one) called AgeGr and the age groups are 18-25...
  4. B

    Why one-tailed sig. in SPSS Regression Correlation

    Given that a two-tailed significance test is usually preferred unless one has a hypothesis about the direction of the relationship, why in the Regression descriptives output does SPSS default to a one-tailed test for the correlations, without any way I can find to change it to two-tailed?
  5. M

    Regression with Differential equations (ODEs / PDEs)

    Hi, in the field of mathematical modelling of biological or physical processes, most of them cannot be described by simple (linear or nonlinear) relationships between predictor X and outcome Y, but only implicitly via differential equations, such as Ordinary differential equations (ODEs) or...
  6. P

    A coefficient to determine Variance

    Hi I am working on a system where temperature stabilises with distance but also increases/ decreases based on month/ hour. Is there a way to tell the model that the variance will decrease with distance? Thanks PYork
  7. S

    Increasing variables decreases DFs?

    I'm sorry if this is a total noob question, but I cannot figure it out. When I'm adding variables into my regression into STATA, the degrees of freedom (and observations) decreases significantly. In particular, adding one variable decreases them by about 1,000. I am only looking at the same 6...
  8. H

    Linear Regression: Disagreement in confounding with stratification

    Hi everyone, I am performing a simple linear regression testing whether an the results from an aptitude test for our sales force is associated with their profitability (binary variable profitable or not). The score variable is a percentile. I performed a simple logistic regression...
  9. J

    Help with Hat Matrix

    considering the model Yi=β0+β1Xi+ϵi, i=1,2,3,…,n how can i calculate the hat matrix and what would element hij be ? thanks
  10. D

    Sample size - have searched high and low,bu tprobarbly very quick and easy to answer!

    Hello Friends, I haven’t looked at a statistics book for a good 5 years, since leaving uni and moving into the job world. However, I have come across a real world problem where I feel there is a statistical method to help me, but after searching high and low cannot find it. I’ve looked at...
  11. L

    NFL Week 6 regression predictions Atlanta 54% NY Jets 79% Pittsburgh 52% Minnesota 73% Buffalo 55% Detroit 84% Denver 75% Houston 55% Miami 52% Seattle 59% Green Bay 80% Baltimore 51% New England 59% Philadelphia 76%
  12. L

    scatter plot for partial regression (in spss)

    Hi all I have an SPSS regression model in which I have a dependent variable, an independent variable and 4 covariates. I want to create a scatter plot for the dependent and independent variables WHILE CONTROLLING for my covariates (the way I understand the default SPSS scatter plot that...
  13. M

    Ordinal regression shows negative effect when spearman correlation shows positive

    I running a regression model where a variable is indicated to have a negative impact on the predicted variable: Estimate Std. Error Wald df Sig. 95% Confidence Interval Lower Bound Upper Bound Threshold [email_contact = 1] -4.682 .664 49.713 1 .000 -5.983 -3.380 [email_contact =...
  14. B

    Leave one out cross validation

    Hi everybody, I've done a linear regression analysis with forward selection method. my number of observations are 32 and the final model selected 2 independents out of 27 variables entered to the regression analysis. now, I am asked to do a leave one out cross validation for checking the...
  15. A

    Linear regression: Prais-winsten method in SPSS with confidence intervals

    Hello Any help greatly appreciated.... I've conducted a linear regression but as the data is autocorrelated (Durbin Watson = 0.5) I wanted to run the Prais-winsten correction. I managed to find the syntax to run that as can't find it in the SPSS menus anywhere but it does not produce...
  16. A

    Alternative for a multi-level analysis

    Hi all, For my criminology thesis I am analysing police interviews and would like to research the effect (the presence of) an attorney has on whether or not a suspect gives a statement. The statement will be a dichotomous variable (0 = remaining silent 1 = giving a statement). My data is nested...
  17. G

    How to correct the means of a variable in 4 groups matlab

    I compute the mean of the variable Y in 4 groups (A B C D) that differ for age, gender and body mass index (BMI). n=89 | n=375 | n=302 | n=166 | GROUP A | GROUP B | GROUP C | GROUP D | MALE 46...
  18. M

    Multiple Regression: 3 levels in IV of interest, how to compare between all 3?

    Hi all, I would like to test the following and am hoping to get some assistance as I am new to regression: DV - Brain volume IV - Participant Group (Patient with Mild Symptoms, Patient with Severe Symptoms, Controls) Covariates - Age, Gender, IQ I wish to use multiple regression in...
  19. 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...
  20. H

    path analysis

    If I wish to do path analysis, how would I put the these variables in a model? I have 2 IVs (e.g. A and B), 1 DV (e.g. C). And A,B and C can be measured using questionnaires. For each variable, A has 2 sub-constructs, (e.g. subA1 and subA2) B also has 2 sub-constructs, (e.g. subB1 and...