Sampling Questions Flashcards
You wish to find out the favourite bands of students in your school. Describe how to take a sample using cluster sapling
Take one class from each year group and sample the students by using a simple random sampling method
A meteorologist wants to know the average temp in their town. The values of the temp, taken hourly over a period of 3 months give an average result of 14. But the average given over a time of 3 years is 21. How reliable are the two methods
The average over 3 months would be bias because it depends on the season of the year. So you would conclude that the average temp is 21.
A student owns 50 books. 20 are in the living room and 30 are in the bedroom. The student wants to sample how many pages are in the books on average. So they take two books from the living room and from the bedroom. Why is this not simple random sampling. Why might this not matter
Because the books in the living room a have a 1/10 chance of being selected, and in the bedroom they have 1/15 chance. These are not equal therefore it is not srs. This will not matter because the rooms do not effect hoe many pages are in the book
The lifetimes of a batch of batteries are measured and listed. Explain why range may not be an appropriate measure of spread.
Because the range may be affected by the outliers so it may not represent the spread of most of the data
