Session 3 Tables in Stata
Importance of tables The analysis of many surveys is primarily Through giving tables And then interpreting the information Simple tables are one-way frequencies Or of percentages Or Multi-way frequencies (or percentages) Tables can also contain summary statistics Like means
Objectives Particiants should be able to Produce tables of each defined type using Stata Interpret data from these tables Produce tables of interest for the data set created for the district in the previous session.
Menus for Stata tables From Statistics Summaries, tables and tests Some commands Table Tabstat Tabsum Tabulate Tab1 To explore table facilities, we will open the data file K_combined_labelled.dta
Menus for Stata tables
Different menu options Match these options to the different types of table that are needed to process survey data
One-way table Open the data file K_combined_labelled.dta Statistics => Summaries, tables & tests => Tables => One-way tables
Results for a one-way table Check you can interpret these results
Multiple one-way tables Statistics => Summaries, tables & tests => Tables => Multiple one-way tables
Tables using commands The commands are simple. For one-way tables try tab q31 For several one-way tables, use tab1, e.g. tab1 region rurban q11 a31 For two-way tables, try tab q11 q16
Try the options Use the dialogue – with the options for Missing and/or sorting Type tab1 q126 q127 q128 q129 q31, missing sort What effects do the options sort and missing have?
Your turn One-way and two-way tables Work through sections 7.1.4 and 7.2 in the Guide. Include 7.2.1 where you check for coding Include 7.2.2 for lists of two-way tables Type tab q31 q126, Then repeat with tab replaced by tab1. Explain the difference between tab1 and tab to your neighbour.
Percentages – interpret results Interpet the results from this table Repeat, but getting column percentages. Interpret those results Hence explain which set of percentages is more appropriate in this table
Multi-way tables Can use tabulate command with by prefix. For example: bysort rurban: tab q128 q11, row Or the “two-way tables” dialogue Or use the more powerful table command table q128 q11, contents(freq) by(rurban) row col Or the “Tables of summary statistics (tables) dialogue See result in next slide
A three-way table Interpret these results Then use the Two-way tables (with By) To give row or column percentages
Second example table q11 rurban q126, by(q16) Use the dialogue or the command table q11 rurban q126, by(q16) Where the row var = Sex (q11) Column variable = Rurban Supercolumn variable = Employed (q126) Superrow variable =Literacy (q16) Interpret the table Try the variables in different orders, to see if your interpretation is simplified
Your turn If you need more time on multi-way tables Then go through Section 7.3 in the guide Then go through Sections 7.4 and 7.5
Tables of summary statistics Section 7.4 and 7.5 consider summary statistics For simple tables they use the tabstat dialogue (or command) Or the table dialogue (or command) is used
Dialogue for tabstat command Menu sequence: Statistics => Summaries, tables & tests => Tables => Table of summary statistics (tabstat) (with Option: Use as columns Statistics)
Summary statistics in a table Note: qd41, qd42, qd43 are expenditures in the previous month for purchase of maize, bean and other seed respectively Omitting the option col(stat) would give the statistics as rows rather than as columns as shown above
Dialogue for table command Menu sequence: Statistics => Summaries, tables & tests => Tables => Table of summary statistics
Summary statistics in a table Discuss with your neighbour the difference between use of tabstat and table .
Further practical work Load your own data into Stata, and produce tables that address an objective of interest that you wish to explore with your data.