multiple regression

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    Can the PCA scores be used as variables in multiple linear regression

    Hello, I used PCA to reduce the dimensions of a data set of 10 variables into 2 principal components (describing 82% of variance in data set of 10 variables) and calculated the scores for both PCs for all the samples (n=85). Can I use these PCs (Scores) (separately or together) as...
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    Using principle component as explanatory variable in multiple regression

    Hello, I used PCA to reduce the dimensions of a data set of 10 variables into 2 principal components (describing 82% of variance in data set of 10 variables) and calculated the scores for both PCs for all the samples (n=85). Can I use these PCs (Scores) (separately or together) as...
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    Multiple Linear Regression Problem

    Hi, I want to do a multiple regression analysis. I have one Y which are numeric values (sample number = 85) and the following Xs. Sr No Variable Data type Data example 1 Region 4 factor levels Region ABC 2 Class 3 factor levels...
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    Plot for multiple regression

    Hi All, I have a very basic question. When I run a regression to predict Y from X, I basically draw a scatterplot in excel. I am wondering how something like that would work when I want to predict Y from X1 AND X2? I am not sure what the best way to plot this relationship. Any...
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    Multiple regression then Sobel for mediation

    Hi, I am doing a mediation analysis. I first ran a multiple regression for IV (2 variables) to mediator. I want to do a Sobel test and use the unstandardized coefficient of the 2 IVs combined. However, I'm not sure where do find that number. Is it the "constant" Is it the R? Is it...
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    multiple regression if one corrleation variable is linear, other is nonlinear

    Hello, I am working on soil biology. I have a data set of soil CO2 emissions (dependant variable), with a number of other measured variables (independents). I expect that one of the independant variables (A) is a straight linear relationship. But expect that another variable (B), is some...
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    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...
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    Sample size calculation for multiple regression

    Hi all! I am struggling with sample size calculations at the minute. I have looked everywhere but all I get is formulas. I have downloaded MedCalc which gives me a number of participants I need per correlation. My supervisor keeps confusing me because she says that it is a different number...
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    Linear regression after multiple regression

    Please excuse my stupidity - would it make sense to conduct linear regression on the predictor variables remaining after backwards elimination in multiple regression? Any help appreciated!
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    coefficient standardization

    Hi All, I am working on a 2nd order regression. The span of coefficient is large (say 1:10000). So the coefficients of 2nd order are very big and not in the same order of the 1st. I think it is needed to implement normalization (both coefficients and data). However, after I did the...
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    Multiple Regression Analysis including Control Variables

    Hi Everyone, Currently I'm working on my masterthesis for which I created a model which was approved by the University. I decided that I want to improve the quality of the model by taking two control variables into account: Age & Organizational tenure. All the variables in this model consist...
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    Hierarchical Regression Analysis - is this the correct technique

    I am proposing a study to find out whether cognitive restraint, disinhibition and hunger predict weight gain in pregnancy. However, I know from previous research that this effect differs depending on BMI category. Am I correct in saying I could use a hierarchical regression analysis, where...
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    Multiple regression,why do we want all coefficients to be significant?

    There is one thing about multiple regression analysis which I do not understand. Lets say your model is Y_{i}=\beta_{0}+\beta_{1}*x_{i1}+\beta_{2}*x_{i2}...+b_{k}*x_{ik}+\epsilon_{i} The \epsilon's are iid normally distributed with mean 0. Then usually the output from computer packages will...
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    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...
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    Length between parameters in Multiple regression

    In multiple regression we know that as an estimate of β and this gives the minimum sum of squares of the residuals: And we know that The question is how to demonstrate that Thanx :)
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    Multiple regression drops variables

    Hi! I am performing a linear multiple regression analysis in spss in 3 steps. In step 1 I entered my control variables (2 interval and 4 dummy variables) using ENTER as the method. In step 2 I entered my 4 dichotomous independent variables, again using ENTER as the method. Finally, in step 3 I...
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    Comparing PCA to multiple regression.

    Dear all, I would appreciate any help on this question. I have been asked to compare the results of PCA to multiple regression. I ve been given 10 variables. For the PCA, i am expected to regress the 3 components that result after the dimension reduction process, and for the multiple...
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    Multple Regression

    I am doing research on the effect of online professional development on educators use of technology in the classroom using the seven constructs of TPACK. Participants have completed a pre and post survey--there are three separate online courses. The following analyses have been conducted...
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    Correlation with control group

    Hi! Sorry if this is a very basic question. If you have two groups: diseased and control. Both groups undergoes an intervention giving you two time points (before and after). Say you measure weight and glucose uptake at both time points, and want to correlate the change in these...
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    How to model large multivariate dataset

    I have a years worth of data at a manufacturing plant with 20 predictor variables and 8 response variables that I'm interested in. A number of the predictor variables have very high multicollinearity. In reality all of the variables are measurements as are the responses i.e. we attempt to set...