1. 12.2 – Analyzing Survey Results

2. Measures of Central Tendency

3. Measures of Central Tendency Mean – the sum of the data divided by the number of items in the data set.

4. Measures of Central Tendency Mean – the sum of the data divided by the number of items in the data set. Median – the middle number of the ordered data or the mean of the middle two numbers.

5. Measures of Central Tendency Mean – the sum of the data divided by the number of items in the data set. Median – the middle number of the ordered data or the mean of the middle two numbers. Mode – the number or numbers that occur most often.

6. Ex. 1 The table shows the number of Calories per serving of each vegetable. Which measure of central tendency best represents the data, if any? VegetableCaloriesVegetableCalories Asparagus14Cauliflower10 Beans30Celery17 Bell pepper20Corn66 Broccoli25Lettuce9 Cabbage17Spinach9 Carrots28Zucchini17

7. Ex. 1 The table shows the number of Calories per serving of each vegetable. Which measure of central tendency best represents the data, if any? 9,9,10,14,17,17,17,20,25,28,30,66 VegetableCaloriesVegetableCalories Asparagus14Cauliflower10 Beans30Celery17 Bell pepper20Corn66 Broccoli25Lettuce9 Cabbage17Spinach9 Carrots28Zucchini17

8. Ex. 1 The table shows the number of Calories per serving of each vegetable. Which measure of central tendency best represents the data, if any? 9,9,10,14,17,17,17,20,25,28,30,66 Since 66 is much larger than the other numbers it would skew the results of the mean. VegetableCaloriesVegetableCalories Asparagus14Cauliflower10 Beans30Celery17 Bell pepper20Corn66 Broccoli25Lettuce9 Cabbage17Spinach9 Carrots28Zucchini17

9. Ex. 1 The table shows the number of Calories per serving of each vegetable. Which measure of central tendency best represents the data, if any? 9,9,10,14,17,17,17,20,25,28,30,66 Since 66 is much larger than the other numbers it would skew the results of the mean. Both the median and mode are 17. VegetableCaloriesVegetableCalories Asparagus14Cauliflower10 Beans30Celery17 Bell pepper20Corn66 Broccoli25Lettuce9 Cabbage17Spinach9 Carrots28Zucchini17

10. Ex. 2 Given the following portion of a survey report evaluate the validity of the information and conclusion. Question: Should the school have an electronic yearbook this year? Sample: Ballots were placed in random students’ lockers. Conclusion: The school should only offer an electronic yearbook this year. ChoiceResponse Electronic only67% Traditional paper22% Offer both9% No preference2%

11. Ex. 2 Given the following portion of a survey report evaluate the validity of the information and conclusion. Question: Should the school have an electronic yearbook this year? Sample: Ballots were placed in random students’ lockers. Conclusion: The school should only offer an electronic yearbook this year. The report does not say exactly how many students were sampled – could be few or many – so the results are not valid in representing the entire school population. ChoiceResponse Electronic only67% Traditional paper22% Offer both9% No preference2%