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Exhibit 3.13 Product A descriptive statistics
3.4.4 Analysis of Cross-Sectional Data—Descriptive Statistics
Our website data is cross-sectional, thus, the time context is not an important
dimension of the data. The descriptive statistics for the old website are shown
in Exhibit 3.14. It is a quantitative summary of the old website data graphed in
Exhibit 3.10. To perform the analysis, it is necessary to rearrange the data shown
in Table 3.2 into a single column of 100 data points since the Data Analysis tool
assumes that data is organized in either rows or columns. Table 3.2 contains data
in rows and columns; thus, we need to stretch-out the data into either a row or
a column. This could be a tedious task if we are rearranging a large quantity
of data points, but the Cut and Pas t e tools in the Home ribbon and Clipboard
group will make quick work of the changes. It is important to keep track of the
100 teens as we rearrange the data, since the old website will be compared to
the new and tracking the change in speciﬁc teens will be important. Thus, what-
ever cutting and pasting is done for the new data must be done similarly for the
old data.
Now let us consider the measures shown in the Descriptive Statistics .Asthe
graph in Exhibit 3.10 suggested, the mean or average for the old website appears
to be between 6 and 8, probably on the higher end given the positive skew of the
graph—the frequency distribution tails off in the direction of higher or positive val-
ues. In fact, the mean is 7.54. The skewness is positive, 0.385765, indicating the
right tail of the distribution is longer than the left, as we can see from Exhibit 3.10.
The measure of kurtosis (peaked or ﬂatness of the distribution relative to the normal
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