st: Fixed Effects inconsistency between Correlation and Coefficient Direction

[MICHAEL ESPOSITO <mespo12@optonline.net>]

I have a question that I cannot seem to find an answer to. I am 
attempting to use the fixed effects model for research that I am 
conducting for my dissertation. My committee and I discovered that in 
certain circumstances the results do not seem logical. For instance, the 
correlation matrix indicates a positive relationship between two 
variables and then when we run the Fixed Effects Linear Regression model 
using the same two variables, the coefficient indicates a negative 
relationship.  I suspect that it may be related to something I read that 
stated that the fixed effects model has the tendency to drop a 
significant amount of data in the independent variable when the data is 
perceived as having a high degree of randomness.

The correlation matrix suggests a positive relationship .2663 and the 
coefficient correlation indicates a negative -1491.  When I run the same 
variables using the linear regression model with the Mixed Effects 
variation, all findings suggest a positive relationship. Does anyone 
know what could be causing this strange occurrence? Any advice or 
guidance you can provide would be most appreciated.
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