Conditional Probability For Statisticians

• Provide at least two examples or problem situations in which statistics was used or could be used.

A statistical example for random variable is coin toss that refers to the discrete random variable as it will get the outcomes in discrete number.

c. What kind of display would you use to show the association between job class and mode of

We, in turn, will make the course as fun and interesting as possible as we introduce

The use of steroids by athletes to gain muscle mass is rapid and effective. Each individual user makes a decision based on the activity they participate. Some athletes desire to jump higher, others to run faster, or to throw the farthest and hit home runs, yet others desire to bench the highest weight possible; and football players want to improve on lean body mass and have a comparative edge, whether in high school, collage, or the pros. Andrew Rensik, of 9BNEWS reports that, "national statistics show that as much as ten percent of high school athletes are involved in steroids" (9NEWS.com). A university of Michigan report by the Monitoring Future Study puts steroid use at 4 percent in 2002, up from 25 percent in 2000. In 1992 71 percent of high school seniors felt that steroid use wasn't worth risking their health, that number dropped to 51 percent in 2002 (www.nsba.org, Ron Kriochic, Mitch Stephens). "Peak rates of annual use occurred in 2002 and 2004 for 12th graders (2.5 percent), in 2000 and 2002 for 10th graders (2.2 percent). Eighth graders reported significant decrease in lifetime and annual steroid use in 2004, as well as a decrease in perceived availability of steroid drugs. A significant decrease was also measured among 10th graders for 2004" (Infofacts 2).

Statistics involves framing questions in a context, then collecting and analyzing data for interpretation. Probability is about chance and fairness with assigned values. Many mathematics instructors teach this discipline in a procedural manner, causing students to miss its essence.

In recent years the number of athletes caught using drugs has increased dramatically. The use of a illegal or unprescribed drugs can cause serious problems and unfairness in many ways. Certain drugs can cause harm to the user and the people around the user, most student athletes do not even know what they are putting into their bodies. With all the risks many persons propose student athletes to be drug tested at random.

This one dealt with an HIV test, which is about 99% accurate. Then a person was selected at random for the test and this person was found to have an HIV positive result. Therefore one naturally assumes the person has a 99% chance of having that disease; but this is wrong. If we then take a larger sample size, the number of possible false positives increase and the probability of that person having the disease also decrease. Here it is important to note that the test itself is accurate, but there is other outside relevant information needed to make the best and most accurate conclusion. The test gave a wrong positive, which is both possible and probable, or the person has the disease; which is also possible and

School teachers and administrators say that drug testing middle school's athletes would aid as a deterrent in the use of drugs for some student athletes according to the New York Times. For example middle school's students are more likely to use marijuana more than steroids or any other drug, but the drug testing works so that they don't do drugs.

The average of 17 results is 60. If the average of first 9 results is 57 and that of the last 9 results is 65, then what will be the value of 9th result?

Drug tests prevent unfairness in sports and negative effects on your body. If you are interested in finding out more about drug tests, ask your team coach and see if the team could start doing drug tests. In addition, you could ask your athletic director at your school to see if your school participates in drug tests. Drug tests should always be required for professional athletes,

P(A | B) is the probability of event A, if we already know that event B has occurred.

-Probability samples are samples that the individuals or items are selected based on the probabilities that are known. A non-probability sample is one where individuals or

We can see from the above that, if one flips a fair coin 21 times, then the probability of 21 heads is 1 in 2,097,152. However, the probability of flipping a head after having already flipped 20 heads in a row is simply 1⁄2. This is an application of Bayes' theorem. This can also be seen without knowing that 20 heads have occurred for certain (without applying of Bayes' theorem). Consider the following two probabilities, assuming a fair coin: • probability of 20 heads, then 1 tail = 0.520 × 0.5 = 0.521 • probability of 20 heads, then 1 head = 0.520 × 0.5 = 0.521 The probability

Police officers are also known to use statistics in several ways, firstly they study crime rates in different neighborhoods to show the need for additional police force. Secondly, to find out what intersections have a high rate for accidents or deaths and are able to watch those intersections and reduce the number of accidents.