When you carry out an investigation, you will collect lots of data which you need to record and then draw conclusions from. This presentation looks at ways of collecting, recording, organizing and interpreting the data.
Using the tally system to record your results is faster than writing out words or figures all the time. If you record your findings in a tally chart, the data is already collected into groups, and you will not need to group it later on. To investigate the most popular color of car passing your house, it is easier to draw tally marks in one of five columns than to write red, blue, silver, silver, red, other, black etc. If you use a tally chart, you could note down the color of the cars as they pass, and find the total frequencies at the end of the one-hour period.Continuous data is data which can take
any worth. Samples include time, height and weight.
As continuous information can take any
value, there are an immeasurable number of likely conclusions. So continuous
data must be grouped before it can be represented in a frequency table or
statistical diagram. For more information please visit http://study.com/academy/lesson/tally-chart-definition-examples.html
-Representing Data In Mathematics-
When you have collected and recorded your data, you can represent it in a diagram. Depending on the results, you can use a frequency diagram, pie chart, line graph, pictogram, frequency diagram, frequency polygon or a scatter diagram.In a bar chart, the height of the bar shows the frequency of the result. As the height of bar represents frequency, label the vertical axis 'Frequency'. The labeling of the horizontal axis depends on what is being represented by the bar chart. A line graph is often used to show a trend over a number of days or hours. It is plotted as a series of points, which are then joined with straight lines. The ends of the line graph do not have to join to the axes. Pictograms use pictures to represent data. To make sense, a pictogram must always have a key. Pie charts use different-sized sectors of a circle to represent data. Scatter diagrams show the relationship between two sets of variables. By looking at the diagram you can see whether there is a link between variables. Where there is a link it is called correlation.
-Measuring Averages In Mathematics-
The mean is the most commonly used measure of average. To calculate the mean, add the values together and divide the total by the number of values. The median is when you place a set of numbers in order, the median number is the middle one. If there are two middle numbers, the median is the mean of those two numbers.The mode is the value that occurs most often. The mode is the only average that can have no value, one value or more than one value. When finding the mode, it helps to order the numbers first.The range is the difference between the highest and lowest values in a set of numbers. To find it, subtract the lowest number in the distribution from the highest.The mean is usually the best measure of the average, as it takes into account all of the data values.However, in order to highlight the differences in the marks scored and to give maximum information, a combination of the median and the range would be best.