Math 37 - HW 5
Practice Assignment (to be discussed Wednesday, Feb. 24)
1) Read the following transcript from Nightline. What blunder or bad assumption is the "expert" making?
TED KOPPEL: Dr. Andrews, I'm sure you have heard such cautionary advice before so on what basis is the assumption being made that this is the one that's going to have the kind of impact on southern California in particular that's being predicted?
RICHARD ANDREWS: Well, in the business that I'm in and that local government and state government is in, which is to protect lives and property, we have to take these forecasts very seriously. We have a lot of forecasts about natural hazards in California and we have a lot of natural events here that remind us that we need to take these forecasts seriously. I listen to earth scientists talk about earthquake probabilities a lot and in my mind every probability is 50-50, either it will happen or it won't happen. And so we're trying to take the past historical record, our own recent experience of the last few years and make the necessary preparedness measures that can help protect us as much as we can from these events.
2) Explain what it means, statistically, to say there is a 30% chance of rain tomorrow.
3) (a) Write down a sequence of H(heads) and T(tails)'s that you think you might get from flipping a coin 100 times (e.g. HHHTH...).
(b) Use Table B, construct an actual sequence of 100 heads and tails (easiest - use even numbers for heads and odd numbers for tails)
(c) What was the longest run of heads (number of heads in a row before get a tail) in your sequence in (a)? In your (b) sequence?
This data will be collected from everyone in class Wednesday!
4) 3.60 (p. 279) Do one repetition, we will pool the results in class Wednesday. Identify the parameter and the statistic in this setting.
Homework Assignment (due Friday, Feb. 26)
1) 3.62 (p. 280) and define the parameter(s) and statistic(s) in this setting.
2) 4.23 (p. 309), showing lots of work and explanations for your calculations.
3) 4.100a, b (p. 366)
4) A die is to be rolled and we are to observe the number that falls face up. The following events will be considered:
A={observe a 6}
B={observe an even number}
C={observe a number greater than 2}
(a) Are events A and B independent? A and C? B and C?
Explain your reasoning.
(b) Are events A and B disjoint/mutually exclusive? A and C? B and C?
If not, explain which outcomes are in both events.
Hint: It might be very helpful to calculate some of the probabilities, please show your work.
5) From Practice Problem #3,
(d) For the class data, how did runs from the two sequences differ? What common perception of probability did this illustrate?