0
votes
0answers
11 views

Under-forecasting in Regression

I have to do forecasting of sales that is how much sales of a product is going to happen in a particular store. I have time series data for last two years and doing forecasting for 2014. The variables ...
7
votes
2answers
266 views

SPSS and Stata output different

I'm Stata-proficient but learning SPSS for my new position. I am using a simple dataset to do very basic regressions and comparing to see if the results are the same. They're not. I'm close, but the ...
0
votes
1answer
29 views

Mixed model in SPSS with random effect and repeated measures

I am working on analyzing a dataset that involves repeated measures data. The data was previously analyzed by a colleague using custom code written in C++, but I have expanded the dataset and am ...
0
votes
1answer
30 views

SPSS: Comparing Regression Coefficient for 2 Models

Hope you guys could help me with a question I've been stuck on for a while. I'm currently writing my thesis on how MRT (the railway system in Singapore) accessibility affects prices of public ...
1
vote
0answers
12 views

some suggestions for analyzing two-factor within subject design?

I'm doing a two-factor within-subject design experiment, and the two factors are all categorical variables. factor one has four categories, while factor two has two categories, and is counterbalanced. ...
0
votes
0answers
12 views

Error messages when doing regression in SPSS

I need to do a number of regressions in SPSS but keep getting error messages. For example - "There are X cells (i.e., dependent variable levels by combinations of predictor variable values) with ...
0
votes
0answers
10 views

Count variable as control variable in regression in SPSS

I'm doing a research on development of audit fees in 2005-2012. I'd like to see if there's a downward or upward trend in them. I have made a count variable of the years (2005=1 2012=8) and now should ...
0
votes
0answers
21 views

General Linear Model (GLM) with Continuous Variable and Categorical Variable (SPSS)

I would like to perform a GLM with a continuous variable and categorical variable as fixed factors. For e.g. Weight predicted by Height and Gender. From what it seems, the univariate GLM option in ...
0
votes
0answers
10 views

hierarchical logistic regression Block non-significant, interaction significant

I'm using hierarchical logistic regression and having some difficulty. Im trying to predict self-harm vs none based on IVs age, gender, alcohol, educational attainment. They are all yes/no except ...
0
votes
0answers
20 views

assess the interaction of two independent variables, on the dependent one

I have a set of laws/policies that overlap with each other through time (for example one started in 1990 and finished in 2001, and the other started in 1995 and finished in 1999). I want to examine ...
0
votes
0answers
8 views

Assistance with hazard ratios

I want to compare car accident deaths in two groups of people aged 18-24 (lets use this as the reference) and 24-30 after a certain law was changed using a Cox hazard model using SPSS version 22. I ...
0
votes
2answers
36 views

Dealing with Categorical variables in Multiple Regression

I have a data having 2 continuous and 4 categorical variables. Each categorical variable has 3 levels. I want to know how to include the variables in the model. I am using SPSS Variables: Sales - ...
1
vote
1answer
169 views

Binary or Multinomial Logistic Regression in SPSS: Interpretation and Reference Categories

I am trying to analyze my data using Multinomial Logistic Regression whereby my dependent variable is a clinical outcome (sick vs healthy) and 1 independent variables (Factors) are in several ...
0
votes
0answers
35 views

Compare regression coefficients within one sample

I run two univariate linear regressions within one sample (same subjects, two different conditions). Now I would like to know how to compare the regression coefficients in order to find out whether ...
0
votes
0answers
16 views

How to get odds ratio when combining multiple tests in logistic regression in spss?

we get odds ratio in logistic regression for predictive accuracy of a test. how do we get one odds ratio from combining more than 1 test in predicting outcome? how do we enter the data to get this in ...
4
votes
1answer
65 views

Principal component regression analysis using SPSS

I have done multiple regression analysis (MLR) of my data and find out $R^2$ and $r$, and then to remove multicollinearity problem I used PCA. This analysis generated PC equal to my variables, I ...
0
votes
1answer
98 views

Leave-one-out cross validation

I am working about elaborate a simple linear regression so I need to evaluate many models. I am asking how I can use leave-one-out cross validation to validate a simple linear regression.
4
votes
1answer
32 views

Predicting variance of heteroscedastic data

I am trying to do a regression on heteroscedastic data where I'm trying to predict the error variances as well as the mean values in terms of a linear model. Something like this: $$\begin{align}\\ ...
2
votes
0answers
35 views

Assessing Cannibalization, intervention of new mobile app on monthly sales

I am a beginner in statistics and looking for suggestions from you all on the approach for one of my study. For my study, there is a company which sells products via its online website (lets call it ...
0
votes
1answer
90 views

Dummy variables in linear regression

I used SPSS to create dummy variables for three different shops. Shop 1 was coded 0, shop 2 was coded 1 and shop 3 was coded 2. In my output I see that the slope coefficients (B) for shop 2 and 3 are ...
1
vote
1answer
56 views

Should I analyze variables separately or together?

I have one categorical variable (on a diet: yes or no) and two numerical variables (patients heart rate and ...
1
vote
1answer
52 views

Book on interpreting plots in regression analysis

I am taking a regression course that is mainly theoretical. But we are given scatter plots and residual plots, and we are supposed to be able to describe the relationships and interpret them. I find ...
1
vote
0answers
43 views

Comparing the difference in change in repeated measures ordinal variables between two groups

I have two groups of patients, those with (OSA) and those without (nOSA) sleep apnoea. Patients were scheduled to undergo a surgical procedure (Sx). Each patient completed a type of quality of life ...
1
vote
2answers
55 views

.999 signifiance query

I am getting the following result for one of my variables after running a logistic regression. Basically I have a set of binary dependent and one independent variable. One of the dependent ...
0
votes
0answers
74 views

Ordinal Independent Variables and Dependent Variable Regression Analysis

I have 3 variables (2 are independent and 1 is dependent). All three variables are measured with questionnaires consisting of multiple questions recorded on 5 point scale. I want to perform regression ...
0
votes
0answers
28 views

Empty significance in SPSS linear regression

I got a weird result with linear regression: there are empty significances. I use 'Stepwise' method, so it should drop the inadequate variables. (Of course the "000" Betas are confusing too.) What ...
2
votes
0answers
38 views

How to test for mediation with a continuous mediator and DV, but a categorical predictor?

I want to explore whether attitudes mediate the relationship between employment status and intention to apply to graduate school. (See image below). I planned to use the Sobel Test to explore the ...
2
votes
1answer
131 views

Building a time series model using more than independent variables

I am working on a project, and I am totally new to statistics. I have sales data for last two years at week level, along with other variables like temperature, holiday (TRUE/FALSE), where holiday are ...
2
votes
3answers
444 views

How can I improve the predictive power of this logistic regression model?

I am using SPSS to analyze a data set which aims to predict whether individuals have cancer based on five symptoms (a, b, c, d, e). In this data set most individuals have cancer. I ran a Binary ...
2
votes
1answer
65 views

SPSS linear regression - variables that are percentages

I have some data about music styles played at festivals. It looks like this: Based on this (and other) data, I'd like to make a model to explain the price of a ticket for each festival. However I'm ...
4
votes
1answer
153 views

Statistical significance for comparison of linear regression models

I have two linear regression models (with the same predictors) that try to estimate two different (although related) features of the same population. I am analyzing the hypothesis that these ...
0
votes
0answers
17 views

Should I include multiple mediating variables in the same analysis?

If the answer is "it depends", what does it depend on? I have three mediating variables, one predictor variable and one outcome variable. I have observed that the results I get when I run three ...
1
vote
0answers
66 views

Discontinuity Regression

I'm writing a political economy Master's thesis regarding the effects of the Euro Crisis on the rise of separatism in Spain (Catalan independence for example). The idea is to show that the Crisis has ...
0
votes
1answer
184 views

How can I compare regression coefficients in the same multiple regression model

I think this question has been answered in bits and pieces here and there, but I am still a bit unsure about what the best approach for this is: how to compare two coefficients from a multiple linear ...
1
vote
0answers
81 views

Questionnaire analysis and grouping responses

I want to know if the creative process engagement (CPE) is related to creativity. I don't know how to analyze the questionnaire. I will be collecting data for CPE with Zhang and Bartal's (2010) ...
0
votes
1answer
73 views

Best way to estimate a regression with reaction times

I have reactions times in a no-normal distribution, so I am using logarithms. Which can be the best way to estimate a regression? Later, I would like to plot the results according to the age of my ...
1
vote
0answers
59 views

Running standardized/unstandardized regression equation on SPSS

I am working on a regression assignment using SPSS. I have raw, centered, and z scores for the data. I already regressed the DV and IV and see the unstandardized and standardized coefficients under ...
1
vote
1answer
147 views

Regression with multiple dependent variables and 2 sets of multiple independent variables

In my data I want to be able to determine which set of IVs (there are 8 variables total, 4 in each set) does a better job of predicting a set a DVs (there are 4). I know I could use multivariate ...
0
votes
1answer
466 views

Marketing Mix Modeling for sales data

I have data for 4 years with variables year, month and sales volume only. I want to find the base volume and incremental volume. I want to use Marketing Mix Modeling. Can anybody tell how to define ...
0
votes
0answers
162 views

Logistic regression model internal validation in SPSS

Please help! I have developed a logistic regression model for prediction of a binary outcome at a range of different times following a set point. This gave me different models with different ...
0
votes
0answers
30 views

spss covariates variables in regression model

in the regression model in the spss statistic software can you explain me what are the covariates variables? if i want express a model like ...
-1
votes
1answer
619 views

Linear/Non-linear Regression - SPSS

Hopefully somebody will be able to shed some light on my SPSS problems! I have been given 65 values. 57 of these data values are quarterly results and 8 are the holdback data to be used. I have to ...
1
vote
2answers
118 views

SPSS Batch Processing Method

I have a more than 150 list of products that will be analyzed by regression method based on years. For example: products: A,B,C ... N (150th products) Then ...
1
vote
0answers
45 views

Multinomial regression analyses

My dependent variable is categorical (with 3 levels) and my predictor variables are a mix of continuous (age in months, test 1 score, test 2 score, test 3 score) and categorical (gender). I believe I ...
1
vote
1answer
114 views

Inverted SPSS results: Logistic regression command vs. Genlin?

I want to do a logistic regression in SPSS. However, since I analyse unemployment spells the subjects are sometimes repeated (violating the independence assumption of the regression). One way of ...
4
votes
3answers
271 views

Pooling regression results in SPSS

I have to solve the following issue: I run my linear regression model many times (let's say 1000 times) with two variables: y - continuous dependent variable, x - continuous independent variable ...
0
votes
0answers
82 views

Transformations used in Automatic Linear Modeling procedure in SPSS

I am using Automatic Linear Modeling in SPSS. Does anyone here know what are the transformations option which is suggested in that procedure?
3
votes
1answer
2k views

Is it acceptable to use linear regression to predict a 4 point likert scale from a 7 point likert scale?

My dependent variable is measured on a 4 point likert scale and independent variable is measured on a 7 point likert scale. Is it appropriate to run regression analysis on such data with varying ...
0
votes
1answer
320 views

What to do when linearity is violated in a linear regression analysis SPSS

I am currently trying to undertake a linear regression analysis in SPSS and I have come across some difficulties. My data does not show linearity and therefore is violated. I have transformed both ...
1
vote
1answer
55 views

How do I check for covariates and how do I adjust for them?

My data: My outcome variable (Outvar) is binary (yes/no) My explanatory variable (exvar) is also binary (yes/no) I have 3 extra variables: Variable A is binary Variable B is continuous but not ...