Hey everyone its Michelle and this is my BOB. When I found out that we were doing statistics I almost freaked out because I know that this unit would be tricky. At the beginning of the unit I was having problems on determining on when to use binomcdf and normalcdf. I thought that I would never understand it. But after going over it many many times it finally makes sense to me. =) I know that when using binomcdf your using it because the data involved is discrete meaning not having a decimal place. For example you couldn't have half a person. And with normalcdf the data involved is continuous which has decimal places. An example would be your weight or your height and both functions you use are commulitive which is when you add up the numbers as you go along. The one thing that still hasn't made complete sense to me is when to use invNorm. So I will definitely have to look into that tonight so that I can do better on the test tomorrow. Good luck everyone, and hopefully we will all do good on tomorrows test!

Hi everyone its me michelle. :) As you all know all that we did today in class was have a pre-test, so as a reminder don't forget to do a BOB! The next scribe is....Alvin

Hello everyone its valley but you also all know me as Michelle. Here's the scribe post for today. In today's class we talked more about z-scores and we learned a couple of new functions on our calculators. Besides using shadeNorm there is another way to figure out the percents of z-scores and that is the commulitive distribution function. Here's an example.

Find the percent of z-scores in a normal standard distribution that are:

a) below z = 0.52

Now to figure this out normally you would press 2nd [vars] and then you would go to the DRAW menu. ShadeNorm is the first function in the menu. After pressing ShadeNorm in the bracets you would enter -5, 0.52. Remember the smallest number is to be entered first. And the reason why you enter -5 is because the curve continues on past the -4 mark for the normal bell shaped curve. So when finished your answer should look like so.

ShadeNorm( -5, 0.52) = 0.6985

Now the new function that we learned today is the commulitive distribution function.

To find this on your calculator you would press 2nd [vars] and its the 2nd function in the menu. It looks like so...normalcdf.

The C stands for commulitive which means you add up the numbers as you go along.

For example if you have a group of 4 then another group of 4 and then a last group of 3 you would add them up as so...4...8...11.

The 2nd function that we learned was the probability distribution function. To find this on your calculator you would press 2nd [vars] and it is the first function in the menu.

The P stands for probability which in this case tells a value at a point.

As I was saying earlier that when using the ShadeNorm or the Normalcdf function you will see that you obtain the same answer.

ex. Find the percent of z-scores in a normal standard distribution that are:

a) below z = 0.52

ShadeNorm( -5, 0.52) = 0.6985
Normalcdf( -5, 0.52) = 0.6985

As you can see your answers are the exact same.

Besides dealing with z-scores again and learning a couple of new functions on the calculator we went over the homework questions from last night. I would try to help and explain them myself but even I am having some difficulties with the problems so I apologize for that. I am gonna get some extra help with that so that the next time I do a scribe I can help everyone out 100%. I hope what i have written has helped you all out. The next scribe is......David-san!

Hey its Michelle and this is my BOB. This unit was based on probability and I found that this unit was more difficult than matrices. The one thing that I'm struggling with in this unit is mutually and non mutually exclusive events, especially in word problems. How do you know when an event is mutually exclusive or not. Are there any key words in the problems that give us hints, and if so what are they? I think that my path to success in this class could be better. I do all my work in class but I need to keep that drive out of school as well. One thing that I think would definitely help me out is if I were to do my homework more often. This way I can get more practice in at the unit we are learning and then I'll be able to understand the material better.