Monthly Archives: March 2018

  • 9

asdoc : options and examples

Category:asdoc,Stata Programs Tags : 

Introduction

asdoc sends Stata output to Word / RTF format. asdoc creates high-quality, publication-ready tables from various Stata commands such as
summarize, correlate, pwcorr, tab1, tab2, tabulate1, tabulate2, tabstat, ttest, regress, table, amean, proportions, means, and many more.
Using asdoc is pretty easy. We need to just add asdoc as a prefix to Stata commands. asdoc has several built-in routines for dedicated
calculations and making nicely formatted tables.

 

asdoc Options

How to enter asdoc options and Stata_command options?
Both the asdoc options and Stata_command specific options should be entered after comma. asdoc will parse both the option itself. For example,the following command has both types of options.

asdoc sum, detail replace dec(3)

option detail belongs to sum command of Stata, whereas options replace and dec(3) are asdoc options.

Following options are used for controlling the behavior of asdoc:

1.1 Replace / append:

We shall use option replace when an existing output file needs to be replaced. On the other hand, we shall use option append if we want to
append results to the existing file. Both the options are optional. Therefore, if none of these options are used, asdoc will first determine
whether a file with a similar name exists in the current directory. If it exists, asdoc will assume an append option. If the file does not
exist, it will create a new file with the default name “Myfile.doc”

Example 1 : running asdoc without replace or append (first time)

sysuse auto
asdoc sum

The above lines of code will generate a new file with the name Myfile.doc. Next, if we estimate a table of correlation, we can replace the
existing file Myfile.doc or append to it. Again, if we do not use any of these options, option append will be assumed. So;

Example 2 : running asdoc without replace or append (second time)

asdoc cor
OR
asdoc cor, append

Both of the above commands serve the same purpose. The file Myfile.doc will now contain a table of summary statistics, followed by a table ofcorrelations. However, had we typed the following, then the file would contain only table of correlations. asdoc cor, replace

1.2 rowappend:

To develop a table row by row from different runs of the asdoc, we need to use option rowappend. This option can be used with ttest, customized summary statistics, or in other instances where the table headers and structure do not change
and appendable statistics have a similar structure as those already in the table.

 

1.3 save (file_name):

Option save(file_name) is an optional option. This option is used to specify the name of the output file. If left blank, the default name will
be used, that is Myfile.doc. If .doc extension is not preferred, then option save will have to be used with the desired extension, such as
.rtf

Example 3 : Naming the output file

asdoc sum, save(summary.doc)
OR
asdoc sum, save(summary.rtf)

 

1.4 title(table_title)

Option title(table_title) is an optional option. This option is used to specify table title. If left blank, a default table title will be
used.

asdoc sum, save(summary.doc) title(Descriptive statistics)

 

1.5 Font size i.e. fs(#)

The default font size of asdoc is 10 pt. Option fs(#) can be used to change it. For example, fs(12) or fs(8), etc.

 

1.6 Decimal points i.e. dec(#)

The default decimal points in many commands are 3. In some commands, the decimal points are borrowed from the Stata output and hence they cannot be changed. In several commands, it is possible to change decimal points with option dec(#). For example, dec(2) or dec(4), etc.

 

1.7 Adding text lines to the output file i.e. text(text lines)

We can write text to our output file with option text(text lines). This is useful when we want to add details or comments with the Stata
output. In fact, this option makes asdoc really flexible in terms of adding tables and paragraph at the same time. We never have to leave the
Stata interface to add comments or interpretation with the results. One trick that we can play is to use option fs() to change font size and
mark headings and sub-headings in the document. Consider the following examples [I have copied some text from www.wikipedia.org for this example]

1. Write a heading "Details on Cars" in our document
asdoc, text(Details on Cars) fs(16) replace

 

2. Now add some text

asdoc, text(A car is a wheeled motor vehicle used for transportation) append fs(10) 
asdoc, text(Most definitions of car say they run primarily on roads, seat one ) append fs(10) asdoc, text(to eight people, have four tires, and mainly transport people.) append fs(10)

 

3. Now add some statistics

sysuse auto, clear
asdoc sum, append fs(10)

 

1.8 Hide Stata output with option hide

We can suppress Stata output with option hide. It is important to mention that option hide might not work with some of the Stata commands (asdoc creates output from log files in some cases).

 

1.9 Getting Stata commands in output files (cmd)

If we need to report the Stata command in the output file, we can use the option cmd.

 

1.10 Abbreviate variable names with option (abb(#))

In case variable names are lengthy, they can be abbreviated in the output file with option abb(#). For example, abb(8). In many cases, the
default value is 10. However, when option label is used, this value is set to = abb + 22

 

1.11 Report variable labels with option (label)

Several commands allow reporting variable labels instead of variable names. For example, the most commonly used commands for reporting statistics are correlate and summarize. Both of these commands allow option label. For example :

asdoc cor, label
asdoc sum, label

 

1.12 Always report equal decimal points (tzok)

The default for report decimal points is to drop trailing zeros and report only valid decimal points. However, we can use the option tzok
i.e. trailing zeros OK, to report equal decimal points for all values even if the trailing values are zero. Therefore, using option
dec(4) for reporting 4 decimal points, the value 2.1 will be reported as follows with and without option tzok.

Default style 2.1
with tzok option 2.1000

 


  • 4

Rolling regressions, beta, t-statistics, and SE in Stata

Category:Uncategorized

asreg can easily estimate rolling regressions, betas, t-statistics and SE in Stata. To understand the syntax and basic use of asreg, you can watch this Youtube video. In this post, I show how to use asreg for reporting standard errors, fitted values, and t-statistics in a rolling window.

To install asreg, type the following on the Stata command window

ssc install asreg

 

Report standard errors and fitted values 

We shall use the grunfeld data set for our examples. Using a rolling window of 15 observations, let us fit a regression model where our dependent variable is invest and independent variables are mvalue and kstock. We shall estimate the rolling regression separately for each company, therefore, we shall use the prefix bys company : 

Please note that option se and fit are used for reporting standard errors and fitted values, respectively.

webuse grunfeld, clear

bys company: asreg invest mvalue kstock, wind(year 15) fit se

 

Find t-statistics in the rolling window

Once we have the standard errors and coefficients, we can generate t-statistics by dividing respective coefficients on their standard errors. Therefore, to find t-values for the variable mvalue and kstock, we can generate new variables:

gen t_mvalue = _b_mvalue / _se_mvalue

gen t_kstock = _b_kstock / _se_kstock



  • 23

Publication quality regression tables with asdoc in Stata – video example

Category:asdoc Tags : 

Creating publication-quality tables in Stata with asdoc is as simple as adding asdoc to Stata commands as a prefix. asdoc can create two types of regression tables. The first type (call it detailed) is the detailed table that combines key statistics from the Stata’s regression output with some additional statistics such as mean and standard deviation of the dependent variable etc. This table is the default option in asdoc. The second table is a compact table that nests more than one regressions in one table (call it nested).

In this video post, I show how to use asdoc to produce the following nested table. 

 

 


  • 4

How to export high-quality table of correlations from Stata to MS Word

Category:asdoc Tags : 

 

For creating a high-quality publication-ready table of correlations from Stata output, we need to install asdoc program from SSC first.

ssc install asdoc, update

Once the installation is complete, we shall add the word asdoc to the cor or correlate command of Stata. Since we estimate correlations among all numeric variables of a dataset with just cor, we shall add asdoc as a prefix to the cor command. For our example, purposes, let us load the auto.dta data from the Stata example files.

 

Example 1: Make a table of correlation for all variables.

sysuse auto, clear
asdoc cor

 

 

Example 2: We can report variable labels instead of variable names

asdoc cor, label replace

 


 

Further, it is possible to write names of the variables in the column headings instead of sequential numbers. For this, we shall invoke the option nonum. Therefore, see example 3.

 

Example 3: Write variable names in column headers

sysuse auto, clear

asdoc pwcorr, nonum replace

 

Read also : 

Table of contents of asdoc

Generate correlation table with significance/stars

Generate a table of descriptive statistics