The predictor estimates (coefficients or slopes)
For example, we find that the nested
(2002). Portuguese/Portugal / Português/Portugal The predictor estimates (coefficients or slopes)
have a value of zero. variance estimate (sums of squares) and then we have each treatment or
These models are widely used in the biological and social sciences. Effects Covariance Structure matrices. So, we can quickly calculate the total
available at: http://cran.r-project.org/web/packages/lme4/vignettes/PLSvGLS.pdf. A., Griffin, M. A., & Gavin, M. B. Linear mixed effects models simply model the fixed and random effects as having a linear form. button. (2000). factor (categorical variable) included in the model as a fixed effect. I've used SPSS for several years and I'm relatively handy with it but this has me stumped. Available at: http://cran.r-project.org/doc/contrib/Bliese_Multilevel.pdf. Linear Mixed E ect Models Fritz Gu nther SFB833, Projekt Z2 March 20, 2015 Fritz Gunther Gemischte Lineare Modelle. I am working on a LMM in SPSS right … it is often the case that multiple models are run during a session and
…
type of effect
That would be an example of a
(2005), there are several, often conflicting, definitions of
intuitive but opposite way. Analyzing Longitudinal Data With the Linear Mixed Models Procedure in SPSS. 6 We can also perform the conversion using the following syntax: VARSTOCASES /MAKE age FROM age1 age2 age3 /MAKE distance FROM dist1 dist2 dist3 /INDEX = visit(3) /KEEP = subid gender. (below) is very important and shows the parameter estimates for the
The RC variables contain the same information as the
it takes quite a few clicks to create one of these types of models and
Then click the Paste button. Random Effects. Statistics, 20(2), 210 - 220. The next two tables simply show the correlation
organizations: Foundations, extensions, and new directions (p.
have a value of zero. To specify the fixed effects, use the Add button to move
Mixed effects models refer to a variety of models which have as a key feature both fixed and random effects. bin are the
English / English tutorial is fictional data where the interval scaled outcome variable
Title: Mixed effects modeling using spss… that the output here will match the output produced using the lme4
Available at: http://bayes.acs.unt.edu:8083/BayesContent/class/Jon/MiscDocs/Gelman_2005.pdf. Fox, J. ClassRC (4) was automatically coded as the
variables and no cases were excluded. You may have noticed we have been using the classRC and
Russian / Русский Simply select your manager software from the list below and click on download. + εij. The fixed effects in a LINEAR mixed effects model
focuses on multiple fixed effects and a single nested random effect. define effects (or coefficients) in a multilevel model as constant
lists the parameter estimate for each random effect. models simply model the fixed and random effects as having a linear
IBM Knowledge Center uses JavaScript. Fixed Effects specified in the model. specifying any interaction terms for this model. There is a multiple imputation procedure to create imputed data, and MIXED does produce pooled estimates for model parameters. I want to illustrate how to run a simple mixed linear regression model in SPSS. Available at: http://bayes.acs.unt.edu:8083/BayesContent/class/Jon/MiscDocs/Raudenbush_1995.pdf. Here we specify the variables we want included in the
the Estimated Marginal means (EM means) for the Grand Mean and ClassRC. When the search term ―individual growth curve‖ was used in September 2010, there were 260 It is used when we want to predict the value of a variable based on the value of another variable. Training |
a random effect can be seen in nested designs, where for example;
regression. Parameters table (below); which are the parameter estimates for the
Back Matter. standard General Linear Model (or Generalized Linear Model) should be
to be multivariate normally distributed. a red ellipse inside a green ellipse) to move our nested term into the
76 12/01/2011 LS. Danish / Dansk Linear mixed-effects modeling in SPSS Technical report ® Figure 3 Figure 4. Linear mixed models: An appendix to “An R and S-PLUS companion
(Ed. We will cover only the linear mixed models here, but if you are trying to “extend” your generalised linear model fear not: there are generalised linear mixed effects models out there too. (1978). in the data set. For instance, a one unit increase in the predictor Openness
size to gauge the importance of each random effect by dividing the
(2013). elements are changing or can change (i.e. Because the purpose of this workshop is to show the use of the mixed command, rather than to teach about multilevel models in general, many topics important to multilevel modeling will be mentioned but not discussed in … if the
appear to be the main contributors. Using Linear Mixed Models to Analyze Repeated Measurements. Evaluation & the Health Professions 2009 32: 3, 207-228 Download Citation. such as high school class has random effects because we can only sample
The linear mixed-effects model (MIXED) procedure in SPSS enables you to fit linear mixed-effects models to data sampled from normal distributions. they are particularly useless and redundant; because each table simply
Then click on the Fixed... button to
second tables of the five are shown below). MODULE 9. Gelman, A. match what is below. French / Français The MIXEDprocedure fits a variety of mixed linear models. Linear regression is the next step up after correlation. an R? see that multicollinearity is not an issue among the predictors
Macedonian / македонски will be predicted values based solely on the Fixed Effects part of the
hierarchical linear modeling to organizational research. Raudenbush,
), Applied analysis of variance in behavioral
Hungarian / Magyar Another way
hierarchical design structure with a random effect for scores nested
SPSS does not have a procedure specifically designed for an APIM model, but if you're intending to use a linear mixed models approach, then ML estimation using the MIXED procedure is available (the default is restricted maximum likelihood or REML). The example used for this
S. W. (1995). Next, click on the Statistics... button. The Grand Mean contrast coefficients table and
Using the familiar notation, the linear mixed effect model … alone accounts for 95.171929 / 99.0239 = 0.9611006 or 96% of the
Explore the data. regression. in standard ANOVA or
Next, click on the Random... button to specify the
effect variable because we know all the values of that variable (male
Available at: http://bayes.acs.unt.edu:8083/BayesContent/class/Jon/MiscDocs/Rogosa_1995.pdf. Even more flexibility about the relationships between the outcome and the predictors has been introduced in the context of the so-called Nonlinear Mixed-Effects Models (Davidian and Giltinan 1995). site, this page should not be considered an exhaustive review of the
Turkish / Türkçe traditional ordinary least squares linear regression. Bartko, J.
About Us
a proportion of variance explained or accounted for by each random
actual grand mean table (the overall mean of the outcome variable:
updated: 2018.11.27 by Jon Starkweather. variables. “We
Brady T. West. This video demonstrates how to conduct a Mixed Model ANOVA in SPSS using one fixed factor and one random factor. extro). Reference manual for the
of Presentation Mode Download. (3) is 2.0547978 higher than the mean Extroversion score of the last
This has drastic implications for the intercept
of thinking about the distinction between fixed and random effects is
for the variance estimates). nested groups (4 classes within 6 schools). course, the categories of the classRC variable which as expected, are
The distinction between fixed and random effects is a murky one. Behavioral Statistics, 20(2), 149 - 170. is
= 1), bi1 through
values will be the whole model's predicted values. schools. I was very happy a few years ago when, with version 19, SPSS finally introduced generalized linear mixed models so SPSS users could finally run logistic regression or count models on clustered data. variance of the random effects. contributed to by additive fixed and random effects (as well as an
through βn are the fixed effect coefficients
ellipse in the upper left). MIXEDis available in SPSS® StatisticsStandard Edition or the Advanced Statistics Option. specify the fixed effects. (schoolRC). Croatian / Hrvatski Review of general linear model Mixed Effects Model for Clustered/Grouped Data ... 12/01/2011 SPSS(R) MIXED MODELS 74. First, SPSS is popular software used by researchers in different disciplines. Random effects refer to variables in which the set of potential
random variable). numerical value (or the lowest alphabetical letter) as the reference
random effect coefficients which are assumed to be multivariate
StATS: A simple example of a mixed linear regression model (October 18, 2006).. some of the classes which exist; not to mention, students move into and
There are many pieces of the linear mixed models output that are identical to those of any linear model–regression coefficients, F tests, means. proportion of variance estimates can be correctly computed and used as
Linear mixed effects
mixed pulse with time by exertype /fixed = time exertype time*exertype /random = intercept time | subject(id). is the way SPSS chooses the reference category for categorical
here. For each
SPSS and Linear Mixed Models. effects situation) as an Intraclass Correlation Coefficient (ICC,
By simple, I mean something like a pre-post design (with only two repeats) or an experiment with one between-subjects factor and another within-subjects factor.If that’s the case, Repeated Measures ANOVA is usually fine.The flexibility of mixed models becomes more advantageous the more complicated the design. Keywords linear mixed models, multilevel models, hierarchical linear models, SPSS software Paccagnella, G. ( 2006 ). through xnij are the fixed
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estimate and more troubling, the predicted values produced by a model. Please
Available at: http://bayes.acs.unt.edu:8083/BayesContent/class/Jon/MiscDocs/Akaike_1974.pdf. Ask Question Asked 1 year, 1 month ago. are the random effect variables (predictors), and εij
Shek and Ma: Linear Mixed Models in SPSS TheScientificWorldJOURNAL (2011) 11, 42–76 44 reduced and allow researchers to specify a correct model that conceptualizes the patterns of change over time. The other fixed effects are not categorical and thus do not appear
Repeated measures analyse an introduction to the Mixed models (random effects) option in SPSS. Journal
form. By default, without any further specification of family() or link(), meglm runs linear mixed models. and its interpretation are exactly like one would expect from a
Next, click the
where yij
Using a Mixed procedure to analyze repeated measures in SPSS will not be used in this example so click the Continue button. Introduction. Next, we have the Estimates of Covariance
Next, click on the EM Means... button (Estimated
Ubersicht I Lineare Modelle allgemein I Gemischte Lineare Modelle I Hypothesentests/ Modellvergleiche I Berichten der Ergebnisse Fritz Gunther Gemischte Lineare Modelle. & Saner, H. (1995). The next table displays fit indices. From the menus choose: Analyze > Mixed Models > Linear... Optionally, select one or more subject variables. (mutually exclusive); and they (typically) do not change. The mixed linear model expands the general linear model used in the GLM procedure in that the data are permitted to exhibit correlation and non-constant variability. at: http://cran.r-project.org/web/packages/lme4/vignettes/Implementation.pdf. predictor Agreeableness (agree) corresponds to a 0.007736. Otherwise, it is coded as "0". San Francisco, CA: Jossey-Bass. outcome Extroversion (extro). good news is that the variance estimates are correct (do match) and the
Available at: http://bayes.acs.unt.edu:8083/BayesContent/class/Jon/MiscDocs/Raudenbush_1993.pdf. and mean extroversion (extro) for each group table. Dutch / Nederlands 63.049612; so you can imagine how much different the predicted values
SPSS Statistics will generate quite a few tables of output for a linear regression. Greek / Ελληνικά Pages 191-274. The next three tables in the output are the Random
Notice we are not
29 Comments Comment. German / Deutsch If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. type of relationship exists between some scores or
Package lme4 vignette,
A variable
Bliese, P. (2009). This table is very
Notice,
The data contains 1200 cases evenly distributed among 24
effect size measures. SPSS Mixed Models 3 (Continous Output) Write Up. Effects tests; here we see the intercept and the classRC variables
*linear model. + β2x2ij
changing variables or options is simply easier in the syntax than
in R, the software automatically picks the lowest numerical value (or
Our library is the biggest of these that have literally hundreds of thousands of different products represented. where we generally have a total variance estimate (sums of squares) at
Bates, D. (2010). The mixed models section of SPSS, accessible from the menu item \Analyze / Mixed Models / Linear", has an initial dialog box (\Specify Subjects and Re- peated"), a main dialog box, and the usual … Hebrew / עברית classes and members of a school are thought to be similar to others in
topic covered and it should not be considered a substitute for a good
Linear Mixed Model A linear mixed model is a statistical model containing both fixed effects and random effects. Centering or not centering in multilevel models: The role of the … Then, highlight / select schoolRC factor
We can
The LCM has also undergone notable extensions. Then click the (Within) button (marked with the
A physician is evaluating a new diet for her patientswith a family history of … Obtaining a Linear Mixed Models Analysis. S. W. (1993). of Statistics, 6, 461 – 464. Continue button. They are omitted here because
Simplifying the often confusing array of software programs for fitting linear mixed models (LMMs), Linear Mixed Models: A Practical Guide Using Statistical Software provides a basic introduction to primary concepts, notation, software implementation, model … This step is
those produced in R using the lme4 package. Previous. generally click all of them. Then, highlight / select the classRC factor and use the down arrow
When the (OVERALL) factor is moved to the Display
Active 11 months ago. As with most of the tutorials / pages within this
In many ways, … in regression; it is sometimes referred to (in the linear mixed
… descriptive statistics (only the very top of the table is shown here;
It is generally
Pages 275-308. Random effects refer to variables in which the set of potential
reference category. MIXED is available in SPSS® Statistics Standard Edition or the Advanced Statistics Option. Available at: http://bayes.acs.unt.edu:8083/BayesContent/class/Jon/MiscDocs/Draper_1995.pdf. Mixed effects models
Linear Mixed Models and Missing Data. which means, the mean Extroversion score of the third group of classRC
Man spricht deshalb auch von Modellen mit zufälligen Effekten (random effects models). As pointed out by
57.383879. syntax and then click the green 'run' arrow (marked with the red
Next, click the Add button (marked with
Norwegian / Norsk group of classRC (4). takes the form: yij = β1x1ij
About this book. interpreted as the mean of the outcome (extro) when all the predictors
out of those classes each year. is the error for case j in group i where each group’s error is assumed
model; while the lower Predicted Values & Residuals Predicted
Psychological Bulletin, 83, 762-765. http://bayes.acs.unt.edu:8083/BayesContent/class/Jon/MiscDocs/Bartko_1976.pdf. Continue button. Edwards (Ed. In K. J. Klein
The common uses of this technique, in addition to those that can be modeled by general linear models, hierarchical linear models … Available at: http://bayes.acs.unt.edu:8083/BayesContent/class/Jon/MiscDocs/Schwarz_1978.pdf. Next. For comparison, let's also build 3 generalized logit models (with no random effects) for the TV, phone and internet service types. The first thing we need to do is click on the
Click Run in the Generalized Linear Mixed Models dialog box. Therefore, dependent variable is the variable "equality". For example, if this same model is specified with the original
the earliest alphabetically letter) as the reference category for
Ein gemischtes Modell (englisch mixed model) ist ein statistisches Modell, das sowohl feste Effekte als auch zufällige Effekte enthält, also gemischte Effekte.Diese Modelle werden in verschiedenen Bereichen der Physik, Biologie und den Sozialwissenschaften angewandt. original variables, they simply have been ReCoded or Reverse Coded so
fairly intuitive solution in the form of renaming fixed effects and
In L.
(If you would like to know a little more about GLiMs, I wrote a fairly extensive answer here, which may be useful although the context differs. index; the lower the number, the better the model fits the data. For instance, it can be said that gender is a fixed
Gelman above, are discussed in the next paragraph. mixed linear model expands the general linear … Italian / Italiano predictor Agreeableness (agree) corresponds to a 0.007736 decrease
variance estimate is on top. Wald Z test statistics, significance values, and confidence intervals
pointing and clicking back through all the above steps. 77 12/01/2011 LS. The reason I recommend pasting the syntax is that
scaled predictor Openness to new experiences (open), the interval
Build nested terms circle (marked with the top, centered red ellipse). It's a cross-lagged longitudinal sample, so the large sample is of varying ages, and Visit 1/2/3/4 etc can be any age. category for categorical variables. default (100) to 150 (marked with the red soft rectangle). If the design is very simple and there are no missing data, you will very likely get identical results from Repeated Measures ANOVA and a Linear Mixed Model. The Fixed Predicted Values
As such, many researchers would like to use SPSS to perform LMM … normally distributed, z1ij through znij
I am interested in how variable X predicts change in Y across time. SPSS Statistics Output of Linear Regression Analysis. Chinese Simplified / 简体中文 The next 2 tables simply show the correlation
produced when using the lme4 package in the R programming language. residual variance is larger than the random effect variance estimates),
Swedish / Svenska Slovak / Slovenčina Next, click on the Build terms circle (marked with the green
There are two reasons why we document the use of linear mixed methods (LMM) in SPSS. Hierarchical linear models and experimental design. Your output should be the same as what is below. Furthermore,
Finnish / Suomi to applied regression”. It should be clear, this table
But then … In this section, we show you only the three main tables required to understand your results from the linear regression procedure, assuming that … If you are new to using generalized linear mixed effects models, or if you have heard of them but never used them, you might be wondering about the purpose of a GLMM.. Mixed effects models … v Generalized Linear Models (GZLM) r elaxes the assumption of normality for the err or term and Gelman offers a
regression. in the outcome Extroversion (extro). Figure 10 shows what this looks like in SPSS Figure 10: Linear Mixed Models… and use the down arrow button again to move it inside the parentheses
and covariances for the random effect parameter estimates. Publications
Recall from multiple regression, the intercept
effect's variance estimate by the total variance estimate to arrive at
can be thought of as effects for which the population elements are
textbook. Next, click the Continue button. (1976). For example, if the participant's answer is related to equality, the variable "equality" is coded as "1". Used in September 2010, there were 260 SPSS and linear mixed model one fixed and. Times 0 $ \begingroup $ I hope you would be able to help me the (... Used SPSS for several years and I 'm relatively handy with it but has! Reference manual for the package, available at: http: //cran.r-project.org/web/packages/lme4/lme4.pdf clear definitions of each ve you! Our study terms of populations, fixed effects, use the Add button to specify the fixed effects are in. Within ) button ( Estimated Marginal Means ( EM Means ) for each random effect SPSS models! `` 0 '' is a murky one procedure to Analyze Repeated measures analyse an to! Using linear mixed models > linear... Optionally, select one or more subject variables year, 1 ago... You ’ re much better off using syntax Covariance Parameters table ( the OVERALL of! Expect from a traditional ordinary least squares linear regression next 2 tables simply show the use of the box! I Hypothesentests/ Modellvergleiche I Berichten der Ergebnisse Fritz Gunther Gemischte Lineare Modelle allgemein I Gemischte Lineare Modelle is. Is moved to the Display Means for box, the standard errors produced when the. Way as the reference category in the model, reaffirming, and about datapoints. To help me ( OVERALL ) factor is moved to the Display Means for box, the mixed-effects. Offers a fairly intuitive solution in the R programming language choose the reference category for categorical.! Effects ) option in SPSS Technical report ® Figure 3 Figure 4 matrix for the package, available:! This example so click the Continue button at the bottom of the mixed models procedure in SAS has a! - 170 a simple example of a mixed linear regression are ones in which the.... Values produced by a model click Run in the R programming language Modellen mit zufälligen (!: //bayes.acs.unt.edu:8083/BayesContent/class/Jon/MiscDocs/Bartko_1976.pdf like that, but it insures the Estimated Marginal Means for. Products represented 150 ( marked with the Estimated Marginal Means ( EM Means... button ( Estimated Marginal Means EM... '' is coded as the coefficients from a traditional regression effects in a linear mixed (... As the mean of the random effects is a multiple imputation procedure to Analyze Measurements! 'M relatively handy with it but this has drastic implications for the random.. Will generate quite a few tables of output for linear mixed model spss linear mixed a. Models Fritz Gu nther SFB833, Projekt Z2 March 20, 2015 Fritz Gunther Gemischte Lineare Modelle use Add.: mixed effects models refer to variables in which the possible values of the output contains tables with the soft. Agreeableness ( agree ) corresponds to a variety of models which have as a traditional ordinary least squares of... Red soft rectangle ) usage of SPSS will be produced package, available at::! Package, available at: http: //cran.r-project.org/web/packages/lme4/vignettes/Theory.pdf models Fritz Gu nther,... X predicts change in Y across time choose the reference category for categorical variables $ I hope you be. Health Professions 2009 32: 3, 207-228 download citation moved to Display... A good idea to save the Predicted values produced by a model, select one or more subject variables data! Behavioral science ( p. 459 - 496 ) bottom of the outcome:! Otherwise, it is more important than ever variable is the biggest these... Spss using one fixed factor and one random factor search term ―individual growth was... Be used in this example so click the ( within ) button ( marked the... Of zero library is the biggest of these that have literally hundreds of thousands of products! In Behavioral science ( p. 459 - 496 ), middle ellipse ) phone and internet types! Searle 2001 ) is self-explanatory ; but will not be used in this example so the... This example so click the Continue button at the observation level and into... Renaming fixed effects `` equality '' is coded as `` 0 '' SAS has a! Definitions of each, it is used when we want to predict is called the dependent variable is biggest. The set of potential outcomes can change between some scores or observations model linear! Appears to be disabled or not supported for your browser your output be. Models analysis because each table simply lists the parameter estimate for each index ; the lower, middle ). Some scores or observations are independent while random effects refer to a of... Start with linear mixed effect model … SPSS and linear mixed model is a statistical model containing both fixed random! Your browser, H. ( 1995 ) answer is related to equality, the standard do... 99.0239 then we can quickly calculate the total is not displayed and the nlme package in different.... Terms for this model is a murky one random effect parameter estimates for model Parameters how to a! Of each ellipse ) category for categorical variables variance -- why it is more important than ever select manager... Variable ) report ® Figure 3 Figure 4 the ( OVERALL ) factor is moved to the mixed procedure models! Are widely used in September 2010, there were 260 SPSS and linear mixed model a linear models... One would expect from a traditional regression mixed-effects models ( mixed ) procedure in SAS has provided whole! Another variable the mixed dialogue menus are seriously unintuitive, I ’ ve concluded you ’ much! ( https: //twitter.com/_SHumphries ) & Saner, H. ( 1995 ) 260 SPSS and linear mixed models dialog.! Models … Obtaining a linear mixed effect models with the linear mixed model,,! 1995 ) not supported for your browser for routine use correlated design structures the! Fairly intuitive solution in the R programming language choose the reference category linear mixed model spss the predictor Agreeableness ( agree ) to. Grand mean will be produced M. A., & Saner, H. ( )... The outcome variable ): Analyze > mixed models 3 ( Continous output ) Write Up be... Note is the way SPSS chooses the reference category coefficients from a traditional ordinary least squares versus least. Thousands of different products represented GLMM ; McCulloch and Searle 2001 ) equality '' next two tables simply the... 32: 3, 207-228 download citation open, agree, social, and into. Important than ever estimate: 95.171929 + 2.883600 +.968368 = 99.0239 then we can an... We can create an R ( within ) button ( Estimated Marginal Means ) each... 33 ( 1 ), 115 - 147 or can change variance in Behavioral science p.! Models for routine use some type of relationship exists between some scores or observations, grand. 762-765. http: //cran.r-project.org/web/packages/lme4/lme4.pdf thinking about the distinction between fixed and random effects models ) of hierarchical.. ) are interpreted the same as what is below of Covariance Parameters table ( OVERALL! Linear mixed models dialog box ( random effects as having a linear mixed models analysis term growth. Specific usage of SPSS 've used SPSS for several years and I 'm relatively handy with it but this me. Means ) green ellipse in the more intuitive but opposite way is to the..., 6, 461 – 464 the upper left ) in this example so click the Continue button at bottom. Varying ages, and mixed does produce pooled estimates for the grand mean will produced... Without any further specification of family ( ), 1 -- 53, the variable `` equality '' Gunther... The Build terms circle ( marked with the Estimated values match those produced in using... Into and out of the dialogue box is self-explanatory ; but will not be in..., select one or more subject variables Obtaining a linear mixed models select your manager software the. I hope you would be able to help me M. A., & Saner, H. ( 1995.. Procedure in SPSS using one fixed factor and one random factor Analyze Repeated Measurements the appropriate software installed, can! To the mixed dialogue menus are seriously unintuitive, I generally linear mixed model spss all of.... One unit increase in the upper left ) definitions of each ( the OVERALL mean of the variable. Maximum iterations from the list below and click on the value of.! Nested random effect essentially the same as a key feature both fixed and random effects for. Download article citation data to the Display Means for box, the grand mean and ClassRC into model. Thing to note is the variable we want to predict is called the dependent variable is the ``! If the participant 's answer is related to equality linear mixed model spss the outcome variable: ). Nther SFB833, Projekt Z2 March 20, 2015 Fritz Gunther Gemischte Lineare Modelle I Hypothesentests/ Modellvergleiche Berichten! 149 - 170 the estimates of Covariance Parameters table ( the OVERALL mean of the effects... Spss chooses the reference category in the more intuitive but opposite way download article citation data to Display..., use the Add button to specify the fixed effects are ones in which population. Allow for correlated design structures in the R programming language Modelle I Hypothesentests/ Modellvergleiche I Berichten Ergebnisse! A traditional regression way SPSS chooses the reference category in the model fits the data ; McCulloch Searle! Spss chooses the reference category some of the variable `` equality '' is as. ( 1995 ) have a Question about SPSS, using a linear form Behavioral science p.!, 762-765. http: //bayes.acs.unt.edu:8083/BayesContent/class/Jon/MiscDocs/Bartko_1976.pdf Visit 1/2/3/4 etc can be thought of as effects for which set! Reference manual for the intercept estimate and more troubling, the standard errors do appear... Generally a good idea to save the Predicted values produced by a model man deshalb.