Tabulation means putting data into tables. A table is a matrix of data in rows and columns, with the rows and the columns having titles.

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2 Tabulation means putting data into tables. A table is a matrix of data in rows and columns, with the rows and the columns having titles. 2

3 converting the set of numbers into the form of a grouped frequency table. This involves dividing the range covered by the data into classes and counting the numbers of data values which fall into each class. These numbers are the class frequencies. 3

4 Lower limits? Upper limits? Class boundary? Class length / width? Class Frequency How many classes should be used but it is usual to arrange for at least 5 and not more than 15. If it can be conveniently arranged for all classes to have the same class width 4

5 Range Cummulative Frequency Less than Less than Less than Less than Less than Less than Less than Less than Less than Less than

6 Data in ordered array: 12, 13, 17, 21, 24, 24, 26, 27, 27, 30, 32, 35, 37, 38, 41, 43, 44, 46, 53, 58 Class Frequency Relative Frequency Percentage 10 but under but under but under but under but under Total

7 In country A there were 22,618,462 dwellings. Of these 9,875,380 were owner-occupied, 6,765,097 were council rentals, 3,476,907 were private rentals and the remainder were held under a variety of tenures. In country B there were 1,846,093 in total and the numbers in the above categories were 569,043, 903,528 and 278,901, respectively. Display this information in a table. 7

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9 The table should be given a clear title All columns should be clearly labeled Where appropriate, there should be clear subtotals A total column may be presented; this would usually be the right-hand column A total figure is often advisable at the bottom of each column of figures Tables should not be packed with so much data that reading information is difficult Non-essential information should be eliminated 9

10 Charts often convey the meaning or significance of data more clearly than would a table. Bar charts Histograms Ogives Pie charts 10

11 A method of data presentation in which data are represented by bars of equal width, the height / length of the bar corresponding to the value of the data. Axes must be labeled and there must be a scale to indicate the magnitude of the data. 11

12 Simple Component Compound A chart consisting of one or more bars The actual magnitude of each item is shown The lengths of bars on the chart allow magnitudes to be compared A bar chart that gives a breakdown of each total into its components. A percentage component = does not show total magnitudes two or more separate bars are used to present sub-divisions of data. There is usually no space between the bars for data in the same category 12

13 A chart which is used to show pictorially the relative size of component elements of a total. (always be based on percentage values) A complete 'pie' = 360 = 100% 180 = 50% Shading and Colour => distinguishes the segments from each other 13

14 Given : Sales of furniture ( 000) Settees 34 Armchairs 27 Dining sets 38 Shelving 18 Others 12 Category Sales Angle, Settees Armchairs Dining sets Shelving Others Total

15 Advantages give a simple pictorial display of the relative sizes of elements of a total show clearly when one element is much bigger than others clearly show differences in the elements of two different totals Disadvantages only show the relative sizes of elements. involve calculating degrees of a circle and drawing sectors accurately can be time consuming unless computer software is used. It is often difficult to compare sector sizes easily. 15

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18 The logic behind this is that there are 360 degrees total in a circle. If you know that 14,400 is 30 percent of the whole (or 0.30), then you're just trying to figure out what 30% of 360 is. Add up all the degrees you calculate from this step. They should equal 360. If they don't, you've missed something. 18

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25 Remember that all good graphs have a title and labels. Add the name of the sections and the percent they represent to the chart. Color each section of the pie chart a different color/pattern to easily visualize the results. Make sure all angles are accurate. 25

26 The area of a bar above a class interval is proportional to the frequency in that class AREA not HEIGHT If there is non-equal size of class interval. Find the frequency density Height of block = class frequency class width 26

27 The following table shows the ages of 25 children on a school bus: Age Frequency (No. of children) Draw a histogram to represent the above data. 27

28 Age Frequency Lower boundary Upper boundary Frequency density

29 The ages of children entering a theme park in a 1-hour period are recorded in the table: Age Frequency (No. of children) Find the class widths and frequency densities. Then draw a histogram to represent the data. 29

30 Constructed from a cumulative frequency table by plotting the cumulative frequencies against the corresponding class boundaries and joining the resulting points by straight lines. 30

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32 Using the data given below, construct a 'more than' cumulative frequency table and draw the Ogive. 32

33 Marks Lower boundary Upper boundary Cumulative Frequency

34 Cumulative frequency 80 'More than' Ogive Marks 34

35 Q: Draw a 'less than' ogive curve for the following data: Hence, from the ogive, estimate the number of students who has less than 57 marks? 35

36 What is the lower boundary and upper boundary of the classes? Marks Lower boundary Upper boundary Cumulative Frequency

37 Cumulative frequency Marks 37

38 A pictogram is a form of graphical presentation where repetitions of a picture are used to represent frequencies or other values of a feature. 38

39 Type of employment Thousands employed Construction Housing Fire Service Health