Using DataData

Why do we need to deal with data ? In the context of what we do in Qatar the answer could perhaps best be ‘To sumarise and present large amounts of data in such a way that others are able to achieve one of the following three aims’.

1) Quickly gain an overview or snapshot of what is happening.

or English results

2) Identify areas of concern or interest e.g. Concern : Class with lower median Interest : Lowest scoring 25 % of students in a particular class

3) Identify trends or improvements e.g.

or

What data should we present and how do we do this ? To do this effectively it is important that you understand your target audience. In Qatar this translates to selecting statistics which can be readily understood and graphs which can be easily explained.

Summary Statistics To describe a set of data normally two numbers are used. CENTRAL MEASURE 1) a CENTRAL MEASURE or single number chosen to represent the entire set. MEASURE OF SPREAD 2) A MEASURE OF SPREAD which, as the name suggests, provides an indication of how the data is spread out.

Central measures averages There are two commonly used central measures or averages meanThe mean calculated by adding all the data points together and then dividing by the number of points. e.g the mean of 6, 7, and 2 is median * The median calculated by putting all the scores in order then finding the middle value. So for the three numbers above the median is 6.

Measures of spread There are also two measures of spread in common use. The Range1) The Range = highest value – lowest value The standard deviation2) The standard deviation which measures how much variation there is from the mean. To calculate from a spreadsheetspreadsheet

Data Display Generally I have used three types of data display which, with some targeted PD, are now understood by the SMT and Staff within the school. These are 1)Box and Whisker plotsplots 2)Strip percentage graphsgraphs 3)Comparative bar graphsgraphs

Summary Statistics Tabulated data can be cut and pasted from the workbook to help provide a better overall picture. Once this has been done I generally include three comments; one relating to medians, the second to the shape of the distribution and the third to the spread. e.g.e.g.

3) Ongoing monitoring of Staff understanding 2) Progressive training of targeted Staff so that by the end of the contract they are self sufficient. 1) Targeted PD for all Staff and members of the SMT to ensure they can understand, evaluate and ultimately use the information in a meaningful way.meaningful way. Sustainability