DataViz Slides Session 3-1.pdf

Data Visualization Session 3 – Part1  1. Connect the data The steps to 2. Explore the Data Source interface visualize data 3. Create data visualizations with Tableau… 4. 5. Create dashboards Create data...

Data Visualization Session 3 – Part1  1. Connect the data The steps to 2. Explore the Data Source interface visualize data 3. Create data visualizations with Tableau… 4. 5. Create dashboards Create data stories Connectthe data You can link (connect)data sources from various locations, including local files and servers After connecting the datasets, you can play around with the data, clean it, integrate various datasets for better insights, etc. The Data Source tab… After loading your dataset(s), a screen tab called Data Source appears It is an interface with various features of the connected dataset(s) Here, you can see how the data tables and variables relate to each other, and change basic features of the data, if needed Create visualizations The workbook interface shows the features required to create visualizations The variables of your dataset appear on the left side The visuals are on the right side under the Show Me section The name of the worksheet can be changed by double clicking on it here Create visualizations The workbook interface shows the features required to create visualizations The variables of your dataset appear on the left side The visuals are on the right side under the Show Me section Create visualizations The workbook interface shows the features required to create visualizations The variables of your dataset appear on the left side The visuals are on the right side under the Show Me section Create visualizations Select data variables to include in the visualization Tableau will highlight the visualizations that are compatible with the variables in the ‘Show Me’ section You must select both descriptive values (dimensions) and metric values (measures)to include in visualizations  The columns in your Excel or CSV data source are shown in Tableau as data fields The sheets in your Excel or CSV data source are Important shown as data tables Each column (data field) is automatically assigned: information A data type (e.g., integer, string, date,…) A role (either a discrete dimension or a about data continuous measure) variables… Dimensions – contain descriptive (qualitative) values (such as names, dates, geographical data,…) that describe the data elements Measures – contain metric (quantitative), numeric values that can be measured Dimensions and Measures in Tableau Dimensions are used to categorize, segment, and reveal details in the data Dimensions affect the level of detail in the view Dimensions are colored blue in Tableau – it creates a header for a view Measures contain the numeric values that measures the quantities of the dimensions Measures are aggregated* (e.g., summed) by default Measures are colored green in Tableau – it creates an axis in the view * NB!What does ‘aggregate’mean? Aggregation in data analytics is like summarizing a big stack of information into something easier to understand. Imagine you have a big pile of receipts from a grocery store. Each receipt tells you what was bought, how much it cost, and the date. If you wanted to see how much you spent in total each month, you wouldn't look at each receipt individually. Instead, you would add up all the costs from each receipt for each month. That process of adding things up to get a total is what we call "aggregation." So, in data analytics, aggregation means combining lots of small pieces of data into a summary form. This helps people see patterns and trends without getting lost in all the details, e.g., Sum: Adding up all the numbers, like total sales Average:Finding the middle value, like the average amount spent per shopping trip Count: Counting how many times something happened, like how many receipts there are Max/Min: Finding the highest or lowest value, like the most expensive item bought By using aggregation, we can quickly understand the overall picture from a large set of data. Using continuous and discrete fields in a view… In Example 1 the Ǫuantity field is Continuous – Example 1 Example 2 it creates a horizontal axis along the bottom of the view (notice the green pill called ‘Ǫuantity’ and the axis in the graph) In Example 2 the Ǫuantity field is Discrete – it creates horizontal headers (notice the blue pill called ‘Ǫuantity’ and the headers) The Sales field is Continuous in both examples – it creates a vertical axis The Sales field is aggregated (indicated by SUM) The items in the Rows will be included on the horizontal axis, while the items in the Columns will be included on the vertical axis. You can change the role of the variable in Tableau if needed! Using continuous and discrete fields in a view… When a measure is dragged to the view, it is aggregated by default The type of aggregation varies depending on the type of view Always check that the aggregation is necessary and change it if needed! Create a dashboard Click the ‘New Dashboard’ tab or choose ‘Dashboard | New Dashboard’ from the drop-down menus Create a dashboard A blank dashboard will appear, with the following sections: A list of existing worksheets in the workbook A selection of additional dashboard elements A layout section, containing the organization of items added to the dashboard A sizing section, for customizing the sizes of the dashboard elements Create a dashboard Tableau places worksheets and associated elements in a strict “no-overlap” order on the dashboard Add the sheets that you want to the dashboard by dragging them into the dashboard space Re-order the items as you want them, and remove clutter that you don’t want… Create a story Click the ‘New Story’ tab or choose ‘Story | New Story’ from the drop-down menus Create a story A blank story will appear, with the following sections: A list of existing worksheets and dashboards in the workbook A selection of additional story elements A layout section, containing the organization of items added to the story A caption section, to give your story a title