Finding Interquartile Range from Dot Plot 1
- 1. - Mr Kim
- 2. Finding IQR for odd number of scores
- 3. 0 1 2 3 4 5
- 4. 0 1 2 3 4 5 Here is a Dot Plot
- 5. 0 1 2 3 4 5 First, find the Median by crossing off the dots
- 6. 0 1 2 3 4 5 Start by crossing off the Bottom dot from the Smallest Score
- 7. 0 1 2 3 4 5 Start by crossing off the Bottom dot from the Smallest Score
- 8. 0 1 2 3 4 5
- 9. 0 1 2 3 4 5 Now cross off the Top dot from the Biggest Score
- 10. 0 1 2 3 4 5 Now cross off the Top dot from the Biggest Score
- 11. 0 1 2 3 4 5
- 12. 0 1 2 3 4 5 Cross off the dots in the directions shown
- 13. 0 1 2 3 4 5 “In”
- 14. 0 1 2 3 4 5 “Out”
- 15. 0 1 2 3 4 5 “In”
- 16. 0 1 2 3 4 5 “Out”
- 17. 0 1 2 3 4 5 “In”
- 18. 0 1 2 3 4 5 “Out”
- 19. 0 1 2 3 4 5 “In”
- 20. 0 1 2 3 4 5 “Out”
- 21. 0 1 2 3 4 5 “In”
- 22. 0 1 2 3 4 5 “Out”
- 23. 0 1 2 3 4 5 “In”
- 24. 0 1 2 3 4 5 “Out”
- 25. 0 1 2 3 4 5 “In”
- 26. 0 1 2 3 4 5 “Out”
- 27. 0 1 2 3 4 5 “In”
- 28. 0 1 2 3 4 5 “Out”
- 29. 0 1 2 3 4 5 Stop here
- 30. 0 1 2 3 4 5 Always stop at “Out”
- 31. 0 1 2 3 4 5 So the Median (Q2) is 3
- 32. 0 1 2 3 4 5 Now divide the Dot Plot in two
- 33. 0 1 2 3 4 5 **It is very important to divide the sides properly
- 34. 0 1 2 3 4 5 To do this, count the dots from the start until you reach the Median
- 35. 0 1 2 3 4 5
- 36. 0 1 2 3 4 5
- 37. 0 1 2 3 4 5
- 38. 0 1 2 3 4 5
- 39. 0 1 2 3 4 5
- 40. 0 1 2 3 4 5
- 41. 0 1 2 3 4 5
- 42. 0 1 2 3 4 5
- 43. 0 1 2 3 4 5
- 44. 0 1 2 3 4 5 Stop here!
- 45. 0 1 2 3 4 5 Now put a Border around the dots that you just counted
- 46. 0 1 2 3 4 5
- 47. 0 1 2 3 4 5 Now put a Border around the other side
- 48. 0 1 2 3 4 5
- 49. 0 1 2 3 4 5 This is how you correctly divide the sides
- 50. 0 1 2 3 4 5 Notice there are 9 dots on each side
- 51. 0 1 2 3 4 5 9 in here
- 52. 0 1 2 3 4 5 And 9 in here 9 in here
- 53. 0 1 2 3 4 5 This is the INCORRECT
- 54. 0 1 2 3 4 5 There are 7 dots in here There are 11 dots in here This is the INCORRECT
- 55. 0 1 2 3 4 5
- 56. 0 1 2 3 4 5 Now find the Median for both sides of the dots
- 57. 0 1 2 3 4 5 Start with this side
- 58. 0 1 2 3 4 5 Remember the directions
- 59. 0 1 2 3 4 5 “In”
- 60. 0 1 2 3 4 5 “Out”
- 61. 0 1 2 3 4 5 “In”
- 62. 0 1 2 3 4 5 “Out”
- 63. 0 1 2 3 4 5 “In”
- 64. 0 1 2 3 4 5 “Out”
- 65. 0 1 2 3 4 5 “In”
- 66. 0 1 2 3 4 5 “Out”
- 67. 0 1 2 3 4 5 Stop here
- 68. 0 1 2 3 4 5 So the Lower Quartile (Q1) is …
- 69. 0 1 2 3 4 5 So the Lower Quartile (Q1) is 1
- 70. 0 1 2 3 4 5 Lower Quartile: 1
- 71. 0 1 2 3 4 5 Lower Quartile: 1 Now do the same to the other side
- 72. 0 1 2 3 4 5 Lower Quartile: 1 Remember the directions
- 73. 0 1 2 3 4 5 Lower Quartile: 1 “In”
- 74. 0 1 2 3 4 5 Lower Quartile: 1 “Out”
- 75. 0 1 2 3 4 5 Lower Quartile: 1 “In”
- 76. 0 1 2 3 4 5 Lower Quartile: 1 “Out”
- 77. 0 1 2 3 4 5 Lower Quartile: 1 “In”
- 78. 0 1 2 3 4 5 Lower Quartile: 1 “Out”
- 79. 0 1 2 3 4 5 Lower Quartile: 1 “In”
- 80. 0 1 2 3 4 5 Lower Quartile: 1 “Out”
- 81. 0 1 2 3 4 5 Lower Quartile: 1 Stop here
- 82. 0 1 2 3 4 5 Lower Quartile: 1 So the Upper Quartile (Q3) is …
- 83. 0 1 2 3 4 5 Lower Quartile: 1 So the Upper Quartile (Q3) is 4
- 84. 0 1 2 3 4 5 Lower Quartile: 1 Upper Quartile: 4
- 85. 0 1 2 3 4 5 Lower Quartile: 1 So the Interquartile Range is: Upper Quartile: 4
- 86. 0 1 2 3 4 5 Lower Quartile: 1 So the Interquartile Range is: Upper Quartile: 4
- 87. 0 1 2 3 4 5 Lower Quartile: 1 So the Interquartile Range is: 4 – Upper Quartile: 4
- 88. 0 1 2 3 4 5 Lower Quartile: 1 So the Interquartile Range is: 4 – Upper Quartile: 4
- 89. 0 1 2 3 4 5 Lower Quartile: 1 So the Interquartile Range is: 4 – 1 Upper Quartile: 4
- 90. 0 1 2 3 4 5 Lower Quartile: 1 So the Interquartile Range is: 4 – 1 = 3 Our Final Answer! Upper Quartile: 4