Hi,
My goal is to measure environmental attitude (EA). To do that I want to construct a scale and use a Rasch model to estimate item and person scores.
My study design is the following.
1. I want to measure EA as a base
2. I want to introduce a cognitive dissonance intervention (or control group)
3. I want to measure EA again to see if the dissonance intervention changed
My hypothesis is contrary to popular opinion.
I expect to not find a significant difference between the 2 conditions for the second measurement and hence additionally no change over time in neither condition (i.e. people do not chance their EA due to the cognitive dissonance intervention).
I have 2 questions:
1. Am I allowed to use the same test in measure 1 and measure 2 or do I have to create parallel forms consisting of different, but similar items?
2. How can I test this hypothesis statistically?
I know, that I can definitely compare the means of both conditions and also I can test if the means changed over time. But I am only familiar with tests that test a statistic difference but with none, that try to identify a null effect, neither between nor within subjects.
If you could help me out, I would be grateful.
Thank you
PS: If possible please share or cite any papers or books that review this topic
My goal is to measure environmental attitude (EA). To do that I want to construct a scale and use a Rasch model to estimate item and person scores.
My study design is the following.
1. I want to measure EA as a base
2. I want to introduce a cognitive dissonance intervention (or control group)
3. I want to measure EA again to see if the dissonance intervention changed
My hypothesis is contrary to popular opinion.
I expect to not find a significant difference between the 2 conditions for the second measurement and hence additionally no change over time in neither condition (i.e. people do not chance their EA due to the cognitive dissonance intervention).
I have 2 questions:
1. Am I allowed to use the same test in measure 1 and measure 2 or do I have to create parallel forms consisting of different, but similar items?
2. How can I test this hypothesis statistically?
I know, that I can definitely compare the means of both conditions and also I can test if the means changed over time. But I am only familiar with tests that test a statistic difference but with none, that try to identify a null effect, neither between nor within subjects.
If you could help me out, I would be grateful.
Thank you
PS: If possible please share or cite any papers or books that review this topic
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