## Tuesday, May 18, 2010

### Measure of Central Tendency

Measure of central tendency
-is a value that represents the center of a set of data
-can be median, mode, mean

-When given a set of data always reorder the digits from least to greatest.

Median
-the middle number in a set of data after the data has been arranged or ordered, only if there is an odd number of items in the dat
a

-if there is an even number of items in the data the sum of the 2 middle numbers in the data set are divided to get the total

eg. 2, 5, 6, 8, 9, -median is 6

1, 3, 6, 8, 9, 10 -median is 7
-----(6+8) ÷ 2 =
7

3, 8, 2, 6, 5, 4, -median is
4.5
2, 3, 4, 5, 6, 8,
----(4+5) ÷ 2 =
4.5

Mode
-the most frequent occurring number in the set of data

-if you find
no number that repeats most often, then there is no mode.

eg. 3, 5, 7, 7, 9 -mode is
7

2, 2, 4, 6, 6, 8, 11 -mode is
2 and 6

1, 2, 3, 4 -mode; there is no mode

Try this:

Montreal scored the following goals in their last 10 games

5, 4, 3, 2, 1, 5, 3, 3, 7, 3

-Find the median and the mode:

1, 2, 3, 3, 3, 3, 4, 5, 5, 7

----------(3+3)
÷ 2
= 3

median-
3
mode-
3

Frequency Table

8, 8, 8, 10, 10, 11, 11, 11, 14, 14

----------(10+11)
÷ 2 = 10.5

median- 10.5

mode- 8, 11

Mean
-a measure of rental tendency

-the sum (adding) of a set of data divided by the number of values in set

eg. 4, 5, 8, 9, 9

- 4+5+8+9+9=35
- 35
÷ 5 =7

Try this- mean, median, mode

a) 4, 5, 6, 7, 7, 8, 8, 9, 9

mean-7, median-7, mode-7

b) 250, 250 300, 300, 400

mean-300, median-300, mode-250, 300

1. I liked your blog Julibella! I think you included everything. My favourite part about your blog was the video, it's very catchy. Keep up the good work! :)

2. Great Job Julibella! very well explained and you even included a video, I dont think your missing anything and what kristel said the song was very catchy GREAT JOB AGAIN!

3. Good Post Julibella. I like how you made different colours when you changed, to a new topic. The one thingi really like was the video. Anyways Excellent Job !

4. Excellent job Julibella! I liked you post, it was organized and well layed out, you included everything we did in class. I like the video you put, I agree with Kristel and Cathlene, the video is very catchy. Great job JB!(:

5. Awesome job Jb! I liked everything about your post. Especially the video. But next time, maybe use more color. Other than that, great job. :D

6. Good post Julibella! I liked the video you added for mean, median and mode. I also liked the information and diagram. Again, great job!

7. Great job! Your post was nice and clear and easy to read and you explained everything clearly too :). and your video was nice too.

8. Great Job ! Your post was easy, and i liked how you found the video that mr.isfield showed us in class, good job. You should add a bit more colour, but either than that Good job !

9. Good Job! The video is good and everything was explained well! Good Job!

10. Good job! You included everything and it was well understood. I also liked the video, very catchy. It never got out of my head once.

11. You did a good job jellybean and I noticed Mr. Issy using that video and you used it to. I'm glad you used it because it's catchy.
-sophia:)

12. Great post. It was very imformative, and you covered all of what we did in class. I liked how you changed the color of titles so they stood out. The song was catchy (too catchy, but that's what it's for, right?). You could incorporate more colour into the post, but you did a great job anyways.=)

13. good job JB you did every hing well the picture, the colour and i liked the song that was on the video. any ways good job!!!

14. great job it was a really good post i liked the colours and the pics!!:)

15. Awesome post! The video was very cool and you had all the the info from the class.

16. Good post Julibella(: I like how you explained what we did during that class and you added a video. Next time, add some colour.

17. Good post Julibella. you explained median mode median i like the video