multiple regression

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    95% Confidence Interval for Regression Coefficients Question

    Hello all, I have been trying to figure out how to answer these homework questions for far too long and happened upon this forum with hopes that I could get a nudge in the right direction…Here is the problem as an attachment. Also included is my work thus far…I think my issue is...
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    Want to plot line to subgroups for relation between one of the IV and the DV

    Hi all, I will try to explain my case as detailed as I'm able to... I have measured on 11 plant species. I want to know the determinants of the time that a pollinator needs to reach the next flower (Time; Dependent Variable). Therefore, I have lumped the 11 plant species, ran a backwise...
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    Interpretaing the coefficients of polynomial regression and multiple regression.

    How do i interpret the coefficients of the 2nd degree polynomial regression model: (crop yield)=1.22+2.1(Nitrogen doses)+3.1(Nitrogen doses)^2 under multiple regression model: (crop yield)=1.22+2.1(rainfall)+3.1(modern tech) Don't think this is a homework.I want the exact interpretation of...
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    Multiple Linear Regression Proof

    Hi everyone, I am enrolled in a regression analysis course at university and the prof really loves to ask for proofs on his assignments. Unfortunately, he never does any in class, and no one at the help centres on campus can ever figure out his problems either. Here is the one I am...
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    Multiple Regression Help

    Hello, I need help/advice with multiple regression analysis. I am looking at the degree of discrimination towards women in construction industry in terms of salary, promotional opportunity, harassment and psychological environment. Data that I have collected are -Age -Level of...
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    Multivariate Regression - comparing two models with different numbers of observations

    Hello, I am attempting to do a multiple regression analysis, but my dataset contains multiple missing values. The values were recoded as ".", but I still cannot get the number of observations to match between the two models and, therefore, cannot run a LRT test. Most of the variables are...
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    Probing an Interaction b/w 3-level categ. predictor and continuous predictor

    Hello! I'm a bit stuck and have scoured the internet for help but to no avail. Any guidance would be much appreciated ... From my omnibus model, I get a significant interaction between my experimental condition assignment (3 level categorical predictor) and Ps' measure of tolerance to...
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    Reporting Beta + unstandardized CIs?

    Hello, I did a multiple regression analysis and for now always only reported the standardized effect sized (Beta). Since I heard that it would be good practice to also include the CIs, I wonder how this is done in practice - should I just present the standardized effect size next to the...
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    Selecting Variables for Multiple Regression (Univariate Significance Levels)

    Hi All! I really hope someone can answer my question. I am building multiple linear regressions and I am testing salient variables one by one at the univariate level to determine whether I should include them. However, what is the current acceptable limits of p values to include/exclude...
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    Confusion over the F-ratio in a hierarchical multiple regression

    Hey all, I'm not used to work with multiple regression analysis, so I would be glad if anyone could help me interpreting this result: I performed a hierarchical multiple regression in SPSS (forced entry) in two Blocks to predict to variable SM: Block 1: Predictors: IQ, AGE Block 2...
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    Urgently need help with data analysis

    Hey folks, i really am desperate for help with this, since I have to present my results at a conference in less than two weeks. I am a statistics-noob undergraduate psychoglogy-student, so please go easy on me. Research and Variables I want to examine the correlative relationship between a...
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    Rank regression --> help!

    I am trying to do a multiple linear regression for a dependent variable Y,with different independent variables X1, X2, X3, etc. I need to use non-parametric multiple regression, as one of my IV, X1, is very skewed and transformation wouldn't help. I was suggested to use Rank regression...
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    Predicting flight performance using personality factors

    I am using HEXACO PI-R as a predictor for flight performance. It contains Honesty-Humility Emotionality eXtraversion Agreeableness (versus Anger) Conscientiousness Openness to Experience with numerous subfactors for each dimension (e.g Emotionality) I want to correlate it to flight...
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    Controlling False Discovery Rate (FDR) in Regression with Correlated IVs

    I am looking for a procedure/code to control FDR in a multiple regression analysis, including 1 DV and 28 IVs (some of them interaction terms). Some IVs are correlated. Where can I find the appropriate FDR procedure/code for this problem? Thanks. Salar
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    Log-Log Multiple Regression - How to incorporate discount + interpreting

    Hello smart people! I am working on a project where I’m trying to understand consumers’ price elasticity, and I was hoping I could get some input from you statistics/econometrics experts (my skills are not very advanced…). I am using historical sales data in order to assess the impact of...
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    Grouping Categorical Variables in Regression differently in Main vs Interactions

    All, I have a very peculiar problem that I am trying to solve. What I mean is, the following is an explanation of the current solution that has been implemented in our group. I am not 100% sure that, in-fact - this is a Statistically valid approach.So, here it goes. Subject Domain - Auto...
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    Which test(s) does SPSS use in a multiple regression analysis?

    Hello, Which test(s) does SPSS use in a multiple regression analysis (MRA)? We can load a data table into it with data types ranging from categorical to continuous, but SPSS doesn't seem to mind. Does that mean that it automatically switches to nonparametric tests if need be, for its MRA?
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    Collinearity Statistics Problem

    Hi everyone, I wonder if anyone would be able to help. I'm running multiple linear regressions and have two independent variables. When looking at the collinearity statistics values, tolerance is .999 for both variables and VIF is 1.001 for both variables as well, which just seems really weird...
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    Multiple regression with a summed, 13-item scale as the DV?

    Hello, As part of my dissertation research I created a scale to measure perceived quality of care. This instrument is comprised of 13 binary items (mostly "Yes/No", but a few "More than expected/Less than expected"), which are then summed to provide a total instrument score. Each item is...
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    Time Series Data- Fish Diet

    My time series spans 13 years. There are 30-60 fish stomachs for each year of the study. Each stomach has typically 3-8 prey items inside. The prey items within the stomachs are the point of interest in this study. I have a plethora of independent variables measured from the capture of all...