# stata

1. ### how does stata calculate confidence intervals for age standardised means/proportions

Dear Stat Talkers! I'm using the following Stata command (see help mean): mean x, std(a) stdw(b) over(c) to get age-standardised mean or proportion of a variable of interest x. a= variable for age-group and b= variable for weights for each group. x can be a continuous variable or a...
2. ### Problems Fitting Latent Growth Curve Model for BMI

Hi all, I have a question regarding panel data--collected biennially--from the National Longitudinal Study of Youth. (I use STATA 13.0 for Mac.) I've been trying--and failing--to fit a latent growth curve model for respondent Body Mass Index (BMI). Respondents were empaneled as children...
3. ### Gravity model with fixed effects - controlling for the heterogeneity

Hi Stata users, I'm quite new to Stata and econometric packages in general, so I'd like to get some hints on how to specify a gravity model for international trade between different countries. My panel consists of 133 countries over 19 years - thus we have 17556 combinations of importers (ci)...
4. ### Guideline to generate a table of Zero Leverage companies

Dear all, I'm new to Stata and i'm trying to learn it. I'm currently working on a research about zero leverage companies and i need to generate a table like the one attached. Since it is my first time i'm experiencing some difficulties. [/url][/IMG] Can anyone give me some...
5. ### Help with interpreting results of a bivariate probit regression please

I have recently run this regression using Stata and the command biprobit. However, I am a complete newbie to statistics and I need some help interpreting the results. I am mostly confused by the Rho and Wald Chi2 results. A simple explanation would be much appreciated. I have attached a...
6. ### Urgent help- statistically significant mean differences

My task is to Test whether there are statistically significant mean differences in the log returns between the y stock and the S&P. The data for which is attached. I have to do all of the analysis in Stata. The data is not normal so I need to do a non-parametric test, I think a Ranksum or...
7. ### Stats Project - Navigating and using Stata.

I am currently attempting a statistics project, using stata, my dataset has four variables and I have the following brief. The data can be seen attached. I have posted the questions, and in brackets said how I think I may go about it. I know this is a lengthy post so sorry for that but any...
8. ### Leontief Inverse using stata - mata

Dear all, We can't manage to generate a Leontief Inverse matrix, below an example. Given for example the following matrix converted from stata. A=st_data(.,("a", "b","c", "d", "e","f")) 1 2 3 4 5 6 +-------------------------------+ 1 | 8 4 5...
9. ### interactions not allowed

i am using a fixed effects model with log of wage as the dependent variable when i try xi: xtreg logwage i.d08##c.yrschool exp2 married, i(id) fe where i.d08##c.yrschool is an interaction term with d08 being a dummy for the year 2008 and yrschool being a continuous variable for years of...
10. ### Help with hazard function plot

Hi, I'm looking for help with hazard function plot. Sample of dataset of 1200 obs: ID Age Drugduration Hypertension Event EventDay Censored 1 76 200 1 0 83 1 2 80 180 0 1 214 0 3 85 120 1 0 275 1 I used these codes: ​ stset EventDay, failure(Event) id(ID) stcox Age...
11. ### Use of holdout cases generated in SPSS in STATA

I am working on consumer preferences for fish, using conjoint analysis. My experimental design was generated in spss using orthogonal design, but my analysis has to be done in STATA. I need clarification if STATA will recognize the holdout cases that would have been used to validate the model in...
12. ### Generating standardized standard errors

I am testing a structural equation model using Stata. I need to report standardized direct, indirect and total effects with associated standard errors (effects decomposition). While I can get the standardized effects, Std. Err. are only generated in relation to the unstandardized coefficients...
13. ### Matrix Multiplication + Save Result by group

Bonjour a tous, I'm trying to achieve the following multiplication VAR = W*S*W' w: [n,1] S: [n,n] s: [n,1] I have the following variables in Stata: date W s In my case, S is a square matrix [n,n] with 1 in the diagonal and a constant (per period) "s" in the diagonal. The...
14. ### Unique combination of variables

Hi guys I have 15000 observations across 7 variables. I need some help with the code to generate all possible unique combinations of variables. e.g. if I had 2 variables and 4 observations per variables V1=a,b,c,d V2=1,2,3,4 Then, combinations = a 1, a 2, a 3, a 4,b 1, b 2, b 3, b 4, c 1, c...
15. ### STATA - Finance - Portfolio Volatility

Hi all, I am experiencing difficulties to calculate portfolio volatility each period ("rebalance") given the following variables (enclosed). Correlation ("corr_Nt") across assets ("ticker") remains constant within a period. It is an equally weighted portfolio but weight changes each period (#...
16. ### STATA - Finance - Portfolio Volatility

Statistical package Please refer to the Statistical Package section for this post
17. ### Import fixed column data help

Hi all, I am having trouble structuring my data so that I can import it into Stata using "infix". I cannot delimit my data as there are blanks that indicate missing values. At present my data looks something like this: ID Age Wealth 1 11 21 2 12 (blank) 3 13 23 Number...
18. ### If statement braces not producing an output

Hello and thanks for your help, I am fairly new to Stata and am having issues trying to get the following if statement to run. When I run the "if statement" from my "do file" it simply shows the code without any changes occurring. I found the only way it will run is if I exclude the...
19. ### HELP! Coefplot: how to display only certain variables?

Hi everyone, I want to use coefplot just to display the coefficients of two categorical variables holding for all the others after a reg. I have saved the output of the regression with est store and then I use coefplot...this is the script reg umeat0 i.soclas6 i.titstu1 i.civstat1...
20. ### Merging PISA waves in Stata

I am running into trouble trying to merge multiple PISA waves into one Stata file for running some hierarchical models. So far, I have combined the student and school files, but do not know the best way for merging 2000 through 2012. The problem is further complicated by the fact that...