Dear all...
I have a series of surveys about the same topic. It is not a panel (longitudinal study) as the individuals change from survey to survey. I have about 15 surveys (from 1995 to 2010). In order to analyse how the individuals' characteristics affect the result on my dependent variable and to analyse some "contextual time effects". I am thinking in running a multilevel regression (aka, mixed model), defining as level 1 the individuals and as level 2 the survey (year) each individual belongs to. Then, I am thinking in analysing how level 2 residuals (after controlling for all relevant individual characteristics) change over time (and if I can explain this level-2 residuals using contextual effects or a time trend). Nevertheless, as my data is not a real panel but a typical case of multilevell (each level-1 individual belongs to only one level-2 unit (the survey)), I am not sure if this approach is right. What do you think? |
Jim,
I may be quite off in right field on this but I'm not sure how much you gain from a multilevel analysis with your data. Not counting aggregate level 1 terms, you seem to have only one level 2 predictor: survey year. More important, you have only 15 level 2 data points which is generally regarded as two few. Joop Hox among others have written on this; however, I don't have specific citations to offer. One thing you should do is check the ICCs. What is the argument that persons in one survey year are more alike to each other than they are to persons on another survey year? I am thinking that your data could be analyzed as a an ordinary regression problem where survey year is another predictor (or a set of contrast terms for survey year). Gene Maguin -----Original Message----- From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of jmdpulido Sent: Tuesday, June 14, 2011 9:19 AM To: [hidden email] Subject: Different Surveys and Multilevel Models (aka mixed models) Dear all... I have a series of surveys about the same topic. It is not a panel (longitudinal study) as the individuals change from survey to survey. I have about 15 surveys (from 1995 to 2010). In order to analyse how the individuals' characteristics affect the result on my dependent variable and to analyse some "contextual time effects". I am thinking in running a multilevel regression (aka, mixed model), defining as level 1 the individuals and as level 2 the survey (year) each individual belongs to. Then, I am thinking in analysing how level 2 residuals (after controlling for all relevant individual characteristics) change over time (and if I can explain this level-2 residuals using contextual effects or a time trend). Nevertheless, as my data is not a real panel but a typical case of multilevell (each level-1 individual belongs to only one level-2 unit (the survey)), I am not sure if this approach is right. What do you think? -- View this message in context: http://spssx-discussion.1045642.n5.nabble.com/Different-Surveys-and-Multilev el-Models-aka-mixed-models-tp4487803p4487803.html Sent from the SPSSX Discussion mailing list archive at Nabble.com. ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Dear Gene,
Thanks a lot for your answer. I was hoping to gaing from multilevel analysis an insight about if personal characteristics have the same effect on my depedent variable over time. I read Joop Hox book some time ago, but I guessed I only focused on territorial examples when I did it. I will check it again looking for a temporal (but no panel) case. I will also try your fixed effects approach of pooling the data and adding a "t" variable for the number of sample and checking its effect. Thanks a lot!!! |
Free forum by Nabble | Edit this page |