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hua
Obsidian | Level 7 hua
Obsidian | Level 7

Does anyone know how to test whether the differences between two regression models are significant?

For example, I have the dataset as follow:

station  year  month  day   Tavg

1          2014     1        1      2.3

1          2014     1        2      3.3

1          2014     1        3      1.3

1          2014     1        4      -0.6

1          2014     1        5      -0.9

1          2014     1        6      2.1

1          2014     1        7      1.8

1          2014     1        8      1.3

1          2014     1        9      2.2

1          2014     1       10     3.2

...

1          2015     1        1      3.2

1          2015     1        2      5.3

1          2015     1        3      2.3

1          2015     1        4      1.4

1          2015     1        5      -2.0

1          2015     1        6      -1.5

1          2015     1        7      0.1

1          2015     1        8      2.3

1          2015     1        9      4.7

1          2015     1       10     5.8

...

2          2014     1        1       6.7

...

 

First, i did a proc reg for each station and each year(model: Tavg= year), so I have one regression model for each year and each station. Then I want to compare the difference between  two regression models under one station to get if it is significant difference between slopes or intercepts. Has anyone know how can I perform this?

 

Thank you for helps!

 

 

2 REPLIES 2
lvm
Rhodochrosite | Level 12 lvm
Rhodochrosite | Level 12

proc mixed ;

class station;

model Tavg = station year year*station / s;

run;

 

Station effect tells you if the intercepts are different for each station. Year*station tells you if the slopes are different.

To get the unique intercepts and slopes, assuming significance, use

model Tavg = station year*station / noint s;

 

 

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What is ANOVA?

ANOVA, or Analysis Of Variance, is used to compare the averages or means of two or more populations to better understand how they differ. Watch this tutorial for more.

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