tailieunhanh - Lecture Research methods - Chapter 8: Data preparation, entry and exploration

Lecture Research methods - Chapter 8 "Data preparation, entry and exploration" presents the following content: Preparing data, inputting and checking data, exploring data, presenting data, introduction to Microsoft Excel. | Data Preparation, Entry and Exploration Samuel K. Frimpong (PhD) Outline of Presentation Preparing Data Inputting and Checking Data Exploring Data Presenting Data Introduction to Microsoft Excel Data Preparation for Analysis As part of preparing your data for analysis, the following should be considered. That is, if you did not consider them before obtaining the data. Type of data (level of numerical measurement) Format in which the data will be input to the data analysis software Impact of data coding on subsequent analyses (for different data types) Need to weight cases Methods you intend to use to check data for errors Data Entry Invariably, all analysis software accept data in “table format” called “Data Matrix” Some primary data collection methods such as CAPI, CATI and online questionnaires can automatically enter and save data in this format. Some secondary data accessed from CD-ROMS can also be saved in this format without the need to re-type. For other data collection . | Data Preparation, Entry and Exploration Samuel K. Frimpong (PhD) Outline of Presentation Preparing Data Inputting and Checking Data Exploring Data Presenting Data Introduction to Microsoft Excel Data Preparation for Analysis As part of preparing your data for analysis, the following should be considered. That is, if you did not consider them before obtaining the data. Type of data (level of numerical measurement) Format in which the data will be input to the data analysis software Impact of data coding on subsequent analyses (for different data types) Need to weight cases Methods you intend to use to check data for errors Data Entry Invariably, all analysis software accept data in “table format” called “Data Matrix” Some primary data collection methods such as CAPI, CATI and online questionnaires can automatically enter and save data in this format. Some secondary data accessed from CD-ROMS can also be saved in this format without the need to re-type. For other data collection methods, you would have to enter the data manually in the data matrix form. Data Matrix Typically, data matrix has rows and columns Each column represents separate variables and each row contains the variables for an individual case id Variable 1 (age) Variable 2 (gender) Variable 3 (level of education) Variable 4 (marital Status) Case 1 1 27 1 2 1 Case 2 2 19 2 1 2 Case 3 3 24 2 3 1 Coding Invariably, all data should be recorded using codes. This enables quick data entry. It also makes subsequent analyses, in particular those that require re-coding of data to create new variables. The scheme for coding is called codebook. Coding Quantifiable Data: The actual numbers are often used. Some numbers can be grouped or combined to form new variables through a process called re-coding Coding Cont’d Coding Categorical Data: existing codes may be used or new scheme of codes designed. Coding of categorical data can be done during the data collection or after data collection. Coding at data collection: