regression

  1. J

    Subset regression error?!

    So I have 11 predictors and one response variable. I am wanting to look at the relationship (see what predictors effect the variable) and as I can't put all my predictors into multiple regression, I thought subsets would be best. Unfortunately when i enter all my data it comes up with the...
  2. M

    Degrees of freedom for an F-test using the Fama-MacBeth procedure

    I am currently writing my master thesis and in the process use the Fama-MacBeth (1973) procedure to obtain risk premia for my factors of interest. Data structure: I have panel data with excess returns for 50 portfolios (my cross-section) for each point in time (time-series). In the same panel...
  3. M

    The difference of means as a fulfilled precondition for a mediation analysis

    The preconditions for a simple mediation analysis according to Hayes (2013) are statistically significant associations between X (the independent variable) and M (the mediator) as well as associations between M and Y (the dependent variable). In the case of a dichotomous independent variable...
  4. P

    Need Help Determining Analysis for Likert Scale Data

    Hello, I need help determining what analysis to run. I have 2 independent variables (a control and experimental condition) with 4 dependent variables (one scale with 4 subscales, each of which I assume should be treated as a dependent variable.) This is Likert data (ordinal) so I thought I...
  5. M

    Test Statistic, how to?!

    x 1, 2, 3, 4, 5 y 35, 14, 21, 28, 7 The book says the test statistic is -1.30 I am getting other answers through my TI 84 and Excel TI 84, I use 2-Sample Test and get -3.6 Excel, using =T.Test two tailed, Paired, I get 0.029 Any suggestions?
  6. D

    Interpret GLM model in test of difference in proportions

    I'm facing the following situation: We conducted a marketing campaign with three groups: 2 test vs 1 of control, where two different type of coupons sent to the two test groups, 3 euros vs. 6 euros. I understand that the best way to test the difference in proportion is a GLM model with binomial...
  7. C

    Correlation and reproducibility

    Hi, I just registered to find some answers to probably very simple questions.. I hope those are not answered too often in the forum, but my computer gives me an error when I try to use the search function (maybe due to corporate internet restrictions). Starting situation 1: 4...
  8. T

    Converting a continuous variable into a categorical variable (low, medium, high)

    I have a continuous dependent variable (scores on an exam) and a number of predictor variables that I'd like to use in a regression analysis, such as gender, age, and income. I'd like to convert age and income into categorical variables: low, medium, and high. I'd like to do this using...
  9. P

    Power analysis for time series regression

    Hello, I'm trying to determine the sample size I need for a study. In the analysis, I will be including three predictors (score on a questionnaire, time, scorextime interaction) and one outcome variable. I am only using one group of individuals and collecting data at baseline, time 1, time 2...
  10. K

    Question on Impact of Independent Variable Interpretation

    Hi, Suppose i have a normal linear regression construct, like Sales = Intercept + M1*X1 + M2*X2 + M3*X3 Suppose X1,X2,X3 are the statistically significant variables from the model. I want to create some sort of a simulator which says , for X% increase in X1, what is increase in Y...
  11. S

    Probability of a subjective event based on historical subjective data . Forecasting

    Lately i developed an idea of understanding the behavior of kids in their childhood. I was wondering how kids are molded into different adults in no time. So i created a problem statement based on my ideology and hoped to solve using applications of mathematics. Coming from a non engineering and...
  12. M

    Regression R2-value Vs spearman correlation coefficient

    Greetings I have been assessing some of the relationships between EDTA extractable Pb Vs Pb in plants etc using regression analysis in minitab. I just found a study that did a correlation analysis instead providing the correlation coefficient and p-value in order to assess if the relationship...
  13. I

    Missing value imputation on a non-normal distribution - EM vs Regression? Or else?

    Hi, Bit green when it comes to some of these methods, so please be gentle... but I'll try to provide as much info and concisely as possible. Any help sincerely appreciated. I have a non-normal dataset with missing at random data and am trying to determine which imputation method to use. I...
  14. E

    PLS regression in SAS, what does corr1 and corr2 refers to?

    Hi all, I am attempting to interpret the results from a PLS-regression done in SAS, and after the analysis SAS produces a table containing two columns labelled as corr1 and corr2. Does anyone know what corr1 and corr2 in the output-table refers to?
  15. T

    Multiple regression V.S. Bivariate regression

    Hi there, I'm interested in the effect of several variables on severity of schizophrenia symptoms. I want to look at the effect of 9 predictor variables in a regression model. Severity of schizophrenia symptoms is the outcome variable. My sample size is about 60. My 9 predictor variables...
  16. A

    Wilcoxon (SL) Regression - Confidence Intervals on Parameter Estimators?

    Does anyone know of a method to create confidence intervals on the SLR parameter estimates of a Wilcoxon Regression model?
  17. M

    Clustering

    i) T/F:Principal Components Analysis can be used to create a low dimensional projection of the data for use with clustering. For this one above, I say its false since PCA doesn't have clustering. Can someone please confirm this? ii) T/F: Factor Analysis and Principal Components Analysis have...
  18. J

    Regression with summated scale help

    Hi all, I am having struggles with computing a (hierarchical) regression analysis for my data, and i have a feeling this is due to my variables. I have a feeling the problem is with my dependent variable - as it is basically a sum of the three categories per respondent. Is there any way that i...
  19. J

    Correlating two pitch contour models

    I am determining tonal ability (the ability to express tones in a tone language, a language which requires a change in pitch to differentiate meaning like Mandarin) by comparing the pitch contour of a non-native speaker to the pitch contour of a native speaker. This means I have two pitch...
  20. T

    Independence of cases (observations)

    Dear all, I am currently analyzing the effects several independent variables have on dependant variable (political party's position on immigration, to be more specific). As the cases (observations) here are political parties - the number of them is very limited (in fact, I have only 21 party...