Descriptive Statistics

In: Business and Management

Submitted By Marameero
Words 856
Pages 4
Given that my population is the students of the first year for academic year 2014-2015 and the variable is their grades in S101 Course and the purpose of that report is studying the trend of their grades. It is important to mention that the Appendix includes some graphs and estimates that have been computed before the study but do not add any additional information that the ones given here like the empirical CDF and the variance.
Graphical and Numerical Representation for the Population:

Figure (1): A histogram showing the distribution of grades of the first year students of 2014.

Interpretation:

* The Histogram is negatively skewed ( it has a long tail extending to the left) which means that the majority of students got grades between 15 and 30 while a small number of them got low grades. This more emphasized by calculating the coefficient of skewness for this variable which is -1.02. * The Histogram is also Unimodal and the modal class is 20- which has a frequency of 101 which means that 101 students got grades from 20 to 25 with a percentage of 43.72% of the total population. (See table 2 in the Appendix). The Mode for this distribution is unique which approximately equals 23. * The mean of such distribution is 21.303 (See Table 1 in the Appendix) which means that the sum of deviations from this number “21.303” equals zero. Furthermore, since this distribution is negatively skewed we previously expect that mean<median<mode. * The distribution appears to be variable where the standard deviation when calculated is 5.014 indicating the variability of such distribution where we have students score zero and others score 30.

To further conclude more information about the grades we can obtain the boxplot.
Figure (2): A Boxplot for the grades in S101 in the year 2014-2015

Interpretation:

* The boxplot emphasizes the fact…...

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