Computer Integrated assessment. Computer integrated assessment Tabulating and graphing of test data.

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1 Computer Integrated assessment

2 Computer integrated assessment Tabulating and graphing of test data

3 Tabulating of data Graphing of data

4 Tabulating of data Reason for tabulating Listing Simple frequency distribution Tabulating & Graphing Grouped frequency distribution

5 Reason for tabulating data To make sense of data. 36 63 51 43 93 54 48 84 36 45 57 45 48 96 66 54 72 81 30 27 45 51 47 63 88 Can you make sense of this data? Tabulating

6 One way to tabulate data. List data in an ascending sequence. List data in a descending sequence. Listing of data 96 72 54 48 43 93 66 54 47 36 88 63 51 45 36 84 63 51 45 30 81 57 48 45 27 27 45 48 57 81 30 45 51 63 84 36 45 51 63 88 36 47 54 66 93 43 48 54 72 96 Ascending sequenceDescending sequence Tabulating

7 Simple frequency distribution XfXfXfXfXfXf 961841721600482362 950830710590471350 940820700580460340 931811690571453330 920800680560440320 910790670550431310 900780661542420301 890770650530410290 881760640520400280 870750632512390271 860740620500380-- 850730610490370-- Tabulating

8 Grouped frequency distribution Step 1: Determine the range of scores R = highest score - lowest score R = 96 – 27 = 69 Step 2: Determine number of intervals Step 3: Divide the range by the number of intervals and round to an odd number i = R = 69/10 = 6,9 (7) number of intervals Step 4: Construct the interval column Step 5: Construct the frequency column Tabulating

9 Grouped frequency distribution Lower limit (LL) Upper limit (UP) 112118 105111 98104 9197 8490 7783 7076 6369 5662 4955 4248 3541 2834 2127 1420 713 Highest score; eliminate intervals above Lowest score; eliminate intervals belowIntervals 91 – 97 84 – 90 77 – 83 70 – 76 63 - 69 56 – 62 49 – 55 42 – 48 35 – 41 28 – 34 21 - 27 Lower limit is a multiple of the interval width. Upper limit is one point less than the lower limit of the next interval. Interval column Step 4: Construct the interval column Tabulating

10 27 45 48 57 81 30 45 51 63 84 36 45 51 63 88 36 47 54 66 93 43 48 54 72 96 IntervalTallyf 91 - 97 84 - 90 77 - 83 70 - 76 63 - 69 56 - 62 49 - 55 42 - 48 35 - 41 28 - 34 21 - 27 2 2 1 1 3 1 4 7 2 1 1 Frequency with Excel Step 5: Construct the frequency column Grouped frequency distribution

11 Graphing of test data The histogram The frequency polygon The cumulative frequency polygon Tabulating & Graphing

12 The histogram The histogram is based on the grouped frequency distribution. Intervalf 91 - 972 84 - 902 77 - 831 70 - 761 63 - 693 56 - 621 49 - 554 42 - 487 35 - 412 28 - 341 21 - 271 f Interval Histogram of test scoresGrouped frequency distribution Graphing

13 The frequency polygon The graph is straight line connecting the midpoint of each interval. Midpoint Frequency polygon of test scoresGrouped frequency distribution IntervalMidpointf 91 - 97942 84 - 90872 77 - 83801 70 - 76731 63 - 69663 56 - 62591 49 - 55524 42 - 48457 35 - 41382 28 - 34311 21 - 27241 Midpoint (MP) = LL + UL 2 f Graphing

14 The cumulative frequency polygon The cumulative frequency polygon is based on the cumulative frequency distribution. IntervalMidpointfcf 91 - 9794225 84 - 9087223 77 - 8380121 70 - 7673120 63 - 6966319 56 - 6259116 49 - 5552415 42 - 4845711 35 - 413824 28 - 343112 21 - 272411 Cumulative frequency distribution Cumulative frequency polygon (OGIVE) Upper level cf GraphingAlternative tutorial