basic concept of data coding

Basic Concept of Data Basic Concept of Data CodingCoding

Codes, Variables, and File StructuresCodes, Variables, and File Structures

Two Ways to Think About CodingTwo Ways to Think About Coding

Coding “ON” the data sourceCoding “ON” the data source Use for unstructured narrative data in digital formUse for unstructured narrative data in digital form Search for themes, key terms and mark on the textSearch for themes, key terms and mark on the text CAQDAS software helps manage the materialCAQDAS software helps manage the material

Coding “FROM” the data sourceCoding “FROM” the data source Use any data source in any form and any languageUse any data source in any form and any language Create a database to collect what you findCreate a database to collect what you find Code what you need from the source into databaseCode what you need from the source into database Manage and analyze the data in the databaseManage and analyze the data in the database

Steps in Coding FROM Data Steps in Coding FROM Data SourceSource

First think about:First think about: How is your source organized in units?How is your source organized in units? What do you want to capture from the units?What do you want to capture from the units?

Then create a structure to hold the data that:Then create a structure to hold the data that: Represents the units in your source Represents the units in your source Contains places to put what you want to captureContains places to put what you want to capture Uses basic rules to keep data organizedUses basic rules to keep data organized

Key IdeasKey Ideas One ROW=One RECORD=One CASEOne ROW=One RECORD=One CASE

One FIELD=One COLUMN=One VariableOne FIELD=One COLUMN=One Variable A flat file holds A flat file holds

records (rows)records (rows)

fields (columns)fields (columns)

Simple Flat FileSimple Flat File

Field 1 Field 1 Field 2Field 2 Field 3Field 3

RecordRecord

RecordRecord

RecordRecord

Flat File RulesFlat File Rules1. Each row or record of data needs a UNIQUE ID 1. Each row or record of data needs a UNIQUE ID

number number

2. Each column or field holds ONE type of information. 2. Each column or field holds ONE type of information. Do not try to put different things into one field.Do not try to put different things into one field.

Why?Why?

3. Data in one field can be plain text, numbers, or can 3. Data in one field can be plain text, numbers, or can have a systematic code have a systematic code

What is the simplest possible code? What is the simplest possible code?

4. Quantitative analysis requires codes or numbers4. Quantitative analysis requires codes or numbers

Can be counted and compared: Can be counted and compared: variablesvariables

Flat File Structure, AgainFlat File Structure, Again

Field 1 Field 1 (Variable 1) (Variable 1)

Field 2 Field 2 (Variable 2)(Variable 2)

Field 3 Field 3 (Variable 3)(Variable 3)

Record 1Record 1(unit #1)(unit #1)



Flat File Structure Aids AnalysisFlat File Structure Aids Analysis

Count # of cases of each category in one fieldCount # of cases of each category in one field

Cross-classify categories in two different fieldsCross-classify categories in two different fields Plot one coded variable against anotherPlot one coded variable against another Standardize raw numbers with percentagesStandardize raw numbers with percentages Perform other forms of quantitative analysisPerform other forms of quantitative analysis

Three Kinds of Flat FilesThree Kinds of Flat Files Spreadsheet (Excel)Spreadsheet (Excel)

Statistical Program (SPSS, SAS, Stata)Statistical Program (SPSS, SAS, Stata)

Relational Database (Access)Relational Database (Access)

THEY LOOK SIMILAR BUT DO DIFFERENT THEY LOOK SIMILAR BUT DO DIFFERENT THINGSTHINGS

What Can You Do in Excel?What Can You Do in Excel?

put data in rows and columnsput data in rows and columns enter text, numbers, dates, and formulasenter text, numbers, dates, and formulas add numbers in column or row (VALUES)add numbers in column or row (VALUES) enter foreign language textenter foreign language text make charts from columns of datamake charts from columns of data import and export data in flat file formatimport and export data in flat file format

What Are Limitations of Excel?What Are Limitations of Excel? row are not stable (oriented to CELLS, not ROWS)row are not stable (oriented to CELLS, not ROWS) difficult to sort, count, manipulate RECORDSdifficult to sort, count, manipulate RECORDS repeat all data entry for each row (but can fill) repeat all data entry for each row (but can fill) spelling errors in entry limit finding and sortingspelling errors in entry limit finding and sorting flat file format itself has limitations for some dataflat file format itself has limitations for some data what if there are multiple instances for one case?what if there are multiple instances for one case?

What Can You do in SPSS?What Can You do in SPSS?

put data in rows that are stable as recordsput data in rows that are stable as records primarily useful for numbers and codesprimarily useful for numbers and codes can separately define and label the codescan separately define and label the codes can count frequencies, do crosstabs, %can count frequencies, do crosstabs, % can collapse or combine codescan collapse or combine codes can do statistical analysescan do statistical analyses

Limitations of SPSS Flat FilesLimitations of SPSS Flat Files need to pre-code data into numeric codesneed to pre-code data into numeric codes need to repeat all code fields for each recordneed to repeat all code fields for each record problems handling multiple instances per caseproblems handling multiple instances per case what if code cannot be developed yet?what if code cannot be developed yet? what if actual words need to be preserved?what if actual words need to be preserved? what if code needs to expand later?what if code needs to expand later?

What Can Relational Database Do?What Can Relational Database Do? create stable records as rowscreate stable records as rows handles numbers, words, dates, noteshandles numbers, words, dates, notes handles foreign languageshandles foreign languages define data types to reduce errors, standardizedefine data types to reduce errors, standardize LINK different files in one-to-many relationsLINK different files in one-to-many relations

simplifies data entry to avoid repeated entrysimplifies data entry to avoid repeated entry can preserve words and develop codes latercan preserve words and develop codes later use lookup tables to standardize codesuse lookup tables to standardize codes

Create forms to simplify data entryCreate forms to simplify data entry Use queries and reports to extract dataUse queries and reports to extract data

Solving Limitations in AccessSolving Limitations in Access

create frequencies and crosstabs with %create frequencies and crosstabs with % use queries for quick and dirty countsuse queries for quick and dirty counts export flat file to SPSSexport flat file to SPSS

make pretty charts to display datamake pretty charts to display data export to Excelexport to Excel export to SPSSexport to SPSS

Do statistical analysisDo statistical analysis export to SPSSexport to SPSS

EXPORT AND IMPORT TABLES OR QUERIESEXPORT AND IMPORT TABLES OR QUERIES

Get Started with a Test SampleGet Started with a Test Sample

find out what is POSSIBLE in your datafind out what is POSSIBLE in your data

what content does it contain?what content does it contain?

what questions could you answer with it?what questions could you answer with it?

how can you extract relevant content?how can you extract relevant content?

how much effort does it take?how much effort does it take?

start with a few cases of the text datastart with a few cases of the text data

Developing Coding SchemeDeveloping Coding Scheme

Think about data source as set of recordsThink about data source as set of records Think about different pieces of informationThink about different pieces of information Think about appropriate way to code eachThink about appropriate way to code each Think about whether data are multilevelThink about whether data are multilevel Work interactively with your dataWork interactively with your data Mistakes are fixable at this stageMistakes are fixable at this stage

A Code is a List of CategoriesA Code is a List of Categories Divides up content in a systematic, meaningful Divides up content in a systematic, meaningful

wayway Gender=Male vs. FemaleGender=Male vs. Female Fruit=Apples, Oranges, Pears, Bananas, OtherFruit=Apples, Oranges, Pears, Bananas, Other

May assign numbers to the categoriesMay assign numbers to the categories Such numbers do not have NUMERIC meaningSuch numbers do not have NUMERIC meaning They simply refer to the different categoriesThey simply refer to the different categories

Coding means assigning content to categoriesCoding means assigning content to categories A data field with coded categories is a “variable”A data field with coded categories is a “variable” Provides a systematic basis for analysisProvides a systematic basis for analysis

Three Ways to Code “Content”Three Ways to Code “Content”

1. Each item is a separate field and is coded 1. Each item is a separate field and is coded present or absent in every record.present or absent in every record.

2. Various mutually exclusive options are 2. Various mutually exclusive options are coded in one field. Each record has one code coded in one field. Each record has one code category.category.

3.Use a sub-table to collect multiple 3.Use a sub-table to collect multiple instances that occur in one record; code in instances that occur in one record; code in sub-table (requires a relational database)sub-table (requires a relational database)

Code What is ThereCode What is There Some data will be missing—too badSome data will be missing—too bad Resist temptation to code only judgmentsResist temptation to code only judgments

Code the evidence into databaseCode the evidence into database Then code your judgment (positive, negative)Then code your judgment (positive, negative) This provides evidence for the judgmentThis provides evidence for the judgment Allows for reliability checks of judgmentsAllows for reliability checks of judgments

Can start with some standard codes, add Can start with some standard codes, add more latermore later

Can enter actual terms, recode laterCan enter actual terms, recode later

Content Coding QuestionsContent Coding Questions

How would you code Male and Female?How would you code Male and Female? How would you code a word or phrase?How would you code a word or phrase?

What if you don’t know all the words now?What if you don’t know all the words now? What if there can be more than one/record?What if there can be more than one/record?

How would you code a topic or theme?How would you code a topic or theme? What if you don’t know all the topics now?What if you don’t know all the topics now? What if there can be more than one/record?What if there can be more than one/record?

Content Coding Questions Content Coding Questions

How would you code Male and Female?How would you code Male and Female? How would you code key words or phrases?How would you code key words or phrases?

What if you don’t know all the words now?What if you don’t know all the words now? What if there can be more than one per record?What if there can be more than one per record?

How would you code a topic or theme?How would you code a topic or theme? What if you don’t know all the topics now?What if you don’t know all the topics now? What if there can be more than one per record?What if there can be more than one per record?

basic concept of data coding

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