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  1. GretaGarbo

    Generating a uniform function from an exponential function

    You will get the U, which has a uniform distribution.
  2. GretaGarbo

    Generating a uniform function from an exponential function

    By using the CDF distribution function! All distribution functions F( ) varies between 0 and 1. So U = F(X) will give you U, an uniformly distributed random variable. Just plug in the x values you have in the CDF and it will give you uniformly values. On the other hand, if you have uniformly...
  3. GretaGarbo

    Which test should be used with 1 dependent variable and 7 independent variables?

    I invite @obh to read Greens textbook about simultaneous equations, chapter 15 from page 382 equation 15-2.
  4. GretaGarbo

    Histogram

    Yes. But not far from normal. Kind of "Bell shaped" (but I dont know if that has a formal definition). To me it looks like negatively skeved. But the mean of this will be approximately normal, is that is what you are asking.
  5. GretaGarbo

    Which test should be used with 1 dependent variable and 7 independent variables?

    You forget about the residuals that infuences H5 and H7. They have an influence on H5 and H7 and there by on y. If you omit these residuals then you have a few omitted variables. What do you mean by "better"? You will not recover the structural relations. Do you mean variance in prediction...
  6. GretaGarbo

    Extrapolation - Getting info of a population from a sample

    No, I should have made an example with say s=6.5. That would have been a better example. Of course sigma is (in general) not known. If sigma happened to be known (maybe from a large population study or many other similar studies) then we would use 1.96*sigma/√(n)
  7. GretaGarbo

    Which test should be used with 1 dependent variable and 7 independent variables?

    Well if you "know" that model 2 is the correct model, then you would like to know the parameter values from that one. That is, you want to uncover the true relations among the variables. Model 1 and model 2 are relatively simple models. y is influenced by H1 to H7, But say H1 is not influenced...
  8. GretaGarbo

    Extrapolation - Getting info of a population from a sample

    No. (I dont know what you mean by "sigma=s*√(n/(n-1)" ) Sigma is the standard deviation in the population. s is the standard deviation in the sample. s is an estimate of sigma. The standard error is s/√(n). That gives the "uncertainty" in the sample mean. Example: The population mean of...
  9. GretaGarbo

    Which test should be used with 1 dependent variable and 7 independent variables?

    I don't understand the question. I just tried to write down the equations for each graphical model Model 2 is a more restrictive model than model 1. Model 2 says how all variables affect the dependent variable y, directly or indirectly. One can say that model 2 is a "structural equation...
  10. GretaGarbo

    Which test should be used with 1 dependent variable and 7 independent variables?

    Well if y is coffee consumption, then model 1 is: y = a+ b1*H1 + b2*H2 +....b7*H7 + residual Then model 2 is a little bit more complicated There are several equations in the model: H5 = a+ b1*H1 + b2*H2 + residual5 H7 = c0 + c1*H3 +c2*H4 + residual7 y = d0 + d1*H5 + d2*H6 + d3*H7 +...
  11. GretaGarbo

    Sample size in proportional tests (prop.test/other suggestions that can include sample size)?

    I did not understan this part. No! Wait! Is the 160 cm the hight above the ground? That would just mean that you have two response variables: y1 = the weight of leaves below 160cm and y2 = the weight above 160 cm. Then you can just do a t-test for each of the variables (or a WMW if you...
  12. GretaGarbo

    Extrapolation - Getting info of a population from a sample

    Just use: m* ± t*s/√(n) where t is from the t-distribution and its degrees of freedom is (n-1). t will be close to 2. :) (Essentially I suggested the t-test! Yeah!)
  13. GretaGarbo

    RESOLVED but still open for discussion: When to transform and when to use non-parametric tests?

    Then we ask the original poster: why were there missing values? (MNAR = missing not at random)
  14. GretaGarbo

    A fund has an annualised Sharpe ratio 3, what is the probability of a negative return for one year?

    Often, people are suggested to be brief. But I think that this is to go too far. (What on earth is an annualized Sharpe ratio 3?)
  15. GretaGarbo

    Which test should be used with 1 dependent variable and 7 independent variables?

    Can you write down the equations for these models? And then, is there anything that prevents you from estimating them?
  16. GretaGarbo

    RESOLVED but still open for discussion: When to transform and when to use non-parametric tests?

    I think that it is better to simply leave the missing values as missing, and to not use then in the testing.
  17. GretaGarbo

    RESOLVED but still open for discussion: When to transform and when to use non-parametric tests?

    But you can not replace a missing value with zero. (If I refuse to tell you my length it does not mean that it is zero.) #change NA’s to 0's my_data[is.na(my_data)] <-‐ 0 It seems like most of your data are positive values. To impose zero values will increase the...
  18. GretaGarbo

    SPSS 24 error "document is already in use"

    Can you open any (other) file? Can you enter a few values and save that in a file? And then open that file?
  19. GretaGarbo

    SPSS 24 error "document is already in use"

    Maybe you are on a network (like a LAN =local area network) and maybe there is an other user that is using that file. Maybe you can copy the file to your own computer and open it from there.
  20. GretaGarbo

    How can I deal with unequal sample sizes in STATA?

    What kind of numbers does that give? So the ESG scores will explain the stock value? So that you have a model like: Stock_value = a + b* ESG + other_things Is not every stock valued at completely different scales? How can you compare them?