Recent content by Stats fan

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    Comparison of beta coefficients within the same group

    I think the Sobel test is what you are looking for: https://en.m.wikipedia.org/wiki/Sobel_test. Also read about its shortcomings and possible alternatives.
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    Which Statistical test is it?

    I think the links can help the OP to learn this, in a different way than the text book does.
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    Which Statistical test is it?

    Is this method selection tool helpful for you? http://statkat.com/statistical-technique-selection/tool-for-selecting-a-statistical-technique-step-one.php You may also like to compare the different tests using these overview tables: http://statkat.com/stattest.php?t=6&t2=8&&t3=9 . You can...
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    How to calculate R^2 from Adj R^2 What is the formula?

    What about R2 = 1 - (1 - AdjR2)*(N - K - 1) / (N - 1)
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    The same SPSS models give DIFFERENT results

    Hi Tim, I think it has to do with missing values. In the analysis with only B as predictor, SPSS omits cases that have missing values on A or B. In the analysis with B as predictor in Block 1 and X as additional predictors in bock 2, SPSS omits cases that have missing values on A, B, or X in...
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    Statistics Homework

    You may like this method selection tool to find out which test is appropriate here: http://statkat.com/statistical-technique-selection/tool-for-selecting-a-statistical-technique.php . The tool will also give you a link to an overview of that test (null and alternative hypothesis, formula, etc.).
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    How do r correlation coefficient and p value connect with N (number of subjects)

    Hint: what are the degrees of freedom? How are the degrees of freedom computed?
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    Please help...

    You may like this method selection tool: http://statkat.com/statistical-technique-selection/tool-for-selecting-a-statistical-technique.php .
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    Analysing nominal and ordinal survey results

    Hello, you may like this method selection tool: http://statkat.com/statistical-technique-selection/tool-for-selecting-a-statistical-technique.php . Only cluster analysis is not included.
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    Intro to stats question

    The t value is equal to t = (xbar1 - xbar2) / sqrt(sp^2 / n1 + sp^2 / n2) The pooled variance sp^2 is equal to sp^2 = (SS1 + SS2) / (n1 - 1 + n2 - 1) = ((n1 - 1)*var1 + (n2 - 1)*var2) / (n1 - 1 + n2 - 1) = ((n1 - 1)*sd1^2 + (n2 - 1)*sd2^2) / (n1 - 1 + n2 - 1) So you are...
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    Intro to stats question

    So your initial conclusion that H0 can be rejected is also correct!
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    Intro to stats question

    Woops sorry, your t of 2.4 was correct... 2.19 is the pooled variance, I misused it as the pooled standard deviataion...
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    Intro to stats question

    Your critical t value and decision rule are now correct. I do get a different observed t value though. Your computations look a bit unclear due to some formatting issues (I think), so it's hard for me to see what went wrong. Here is my computation of t: t = (13.7 - 12.5) / sqrt(2.19^2/16 +...