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Welcome to  Humber Libraries video on reading a cross table in  
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Vividata. For a more general introduction to the  tool, see our Introduction to Vividata video.   
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This video will show you how to read  a cross table to answer the question,  
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What is the most popular phone brand  for Toronto Residents in Generation Y?  
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To see how this table was generated, watch our  video on creating cross tables in Vividata.   
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This table shows that 47.3% of Toronto  residents in Generation Y have an Apple iPhone,  
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making it the most popular phone in  the city. To accurately read a table in  
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Vividata the percentage and Count must always  be read as a fraction of the column headings.  
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This is called a vertical percentage  because it is first read vertically.   
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Start with the 47.3% , then continue moving up  to read the column headings to create, 47.3%  
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of Toronto residents in Generation Y. Only then do  you finish by reading the row that the 47.3 is in.  
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This creates the phrase, 47.3% of Toronto  residents in Generation Y own an iPhone.   
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Be careful not to read the table horizontally,  such as, 47.3% of iPhone owners are Toronto  
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residents in Generation Y. These phrases seem  interchangeable, but they are not. To find the  
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correct answer to the horizontally read phrase  would require building a whole new table.   
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To read the entire table, start  at the top of the table.   
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This example table includes the 14+ variable as  a row (or question) and as a column (or split).  
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This variable represents all  the participants in the survey.  
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It is okay to leave these variables in the  table because they add context when reading  
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the results. Next, read the column headings  of the table. In this example the headings,  
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or splits, are nested. You can tell this because  they are positioned on top of each other.   
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The first heading 14+ tells us the variable  which contains all the respondents to the survey.  
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The next heading, 14+ indicates  that for this variable,  
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the only possible answer is included - everyone  over 14 years of age. The next variable heading,  
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Demographics\Age/Generation-Generation tells  us that this variable contains answers that  
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split the survey respondents into generations of  people. The next heading, Gen Y (born 1980-1995)  
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is the selected answer for the  Demographics\Age/Generation-Generation  
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variable. The next heading,  Demographics\Geography-Sub-markets  
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is a variable name that indicates that its answers  will be geographic sub-markets of Canada.   
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And then the next heading, City of Toronto is  the answer that has been selected from that  
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variable. When reading the nested headings,  it is important to note that the population  
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represented by the table becomes a smaller as more  variables are nested underneath each other.   
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It s also important to note that 14+,  Demographics, Age/Generation, Generation,  
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and Demographics\Geography-Sub-markets are  the variables, and that for each of them  
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we have decided to display only one answer.   Sometimes when building a table you may choose  
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to display many answers for a single variable,  as is the case with our mobile phone variable.   
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There are two more headings at the top of  the table, they are Count and Percent .  
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The numbers under the Count column tell you the  number of people, multiplied by 1000, represented  
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when reading that row. For example, the first  row in the table is labelled, 14+ , then 14+ ,  
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and then in the Count column, the number 767.   
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This tells us that there are 767,000 Toronto  residents in Generation Y who are over 14.   
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Moving over one column to the % , the 100% tell us  that the 767,000 Toronto residents in Generation Y  
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make up the entire population being examined in  this table. All of the other percentages in  
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the table will be fractions of the 767,000 Toronto  residents in Generation Y. For example, the count  
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beside the Apple answer is 315,000. If you divide  315,000 by 767,000 and then multiply by 100,  
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the result, 41, is the percentage of Toronto  residents in Generation Y with an iPhone. This  
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percentage is not in the table, and this is why  it is valuable to know how to read the counts.   
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The 47.3% in the Apple row is the percentage  of mobile phone-owning Toronto residents in  
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Generation Y with an iPhone. To calculate this  percentage, you would divide 315,000 by 666,000.  
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The 666,000 is the Weighted base located in the  second to last row of the Digital Devices/Mobile  
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Phone \Mobile Phone-Brands  Personally-Have variable.   
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This distinction can be confusing but it helps  us understand the tables Vividata generates.  
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The Weighted base that is part of the 14+ variable  represents all the Toronto People in Generation Y.  
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The Weighted base that is part of the Digital  Devices/Mobile Phone \Mobile Phone-Brands  
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Personally-Have only represents Toronto People  in Generation Y who have a mobile phone of any  
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kind. At this point you may be wondering what  it means for there to be both a Weighted base  
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and Unweighted base for the row variables.  To understand these, start by considering  
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how difficult it would be for Vividata to  conduct a survey whose respondents match the  
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proportion of the population exactly. That is, if  the population of the City of Toronto is about 30%  
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Generation Y, then it would be difficult to make  sure that 30% of your survey respondents are  
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people in Generation Y. It is more likely that  due to random fluctuations the survey will capture  
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20% to 40%, by proportion, of  Toronto s People in Generation Y.  
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To correct for this, Vividata does some math to  their raw survey counts to ensure they match the  
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real proportions. In the context of the table, the  Unweighted base is the raw number of responses.  
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The Weighted base is the number that has  been mathematically adjusted to match the  
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correct proportions of the population. This  video showed you how to answer the question,  
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What is the most popular phone brand for Toronto  residents in Generation Y? by reading a generated  
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cross table. For more on this tool, watch  the other videos in our Vividata series.