Q. I have been given the the question do cars from origin B have better fuel consumption than cars from origin A. I have been given the Means (A=13.04, B=7.89) the SD (A=4, B=1.68). It was a Simple random sample of 303 cars (A=239, B=73). I need to find the test statistic and P-value, and show working and evidence for my answer.
Answer
This is a difference in means tests (u1-u2). If the SD is the population sd, then you would use the z test. If it's the same sd, then you would the t test that doesn't use the pooled sd. You can find the respective formula in your book.
You have to be more specific when providing information for your question. When you say mean, doesn't that mean average miles per gallon? meaning 13 would be better fuel consumption than 7? Or does having a lower number mean better fuel consumption?
I'm going to assume it's the former. If it's the latter, just switch everything I say.
Now you want to test if B has better consumption. So you want to see if mean of A < mean of B. (I will write this as ua <ub.
So your hypothesis would be
Ho: ua - ub = 0
H1: ua < ub or ua - ub < 0
I'm assuming the sd's are the sample sd. If so, plug in all the info into the t test formula.
It should be something like [(x1-x2) - (u1-u2)]/sqrt(s1^2/n1 + s2^2/n2)
You have all the info provide. x1=13.04 s1^2=4^16 n1=239 u1-u2=0
You will now have your t score.
Figure out the degrees of freedom. It's either going to be n1+n2 - 2 or some weird long formula. I dont remember which one it was exactly. You should be able to find it in your book.
Now you should know that this is a one tailed (left) test because of the < in the h1.
Go to your t chart and figure out the p value.
If your sd's were population sds, then you would do the same thing, but use the z test and the z chart.
This is a difference in means tests (u1-u2). If the SD is the population sd, then you would use the z test. If it's the same sd, then you would the t test that doesn't use the pooled sd. You can find the respective formula in your book.
You have to be more specific when providing information for your question. When you say mean, doesn't that mean average miles per gallon? meaning 13 would be better fuel consumption than 7? Or does having a lower number mean better fuel consumption?
I'm going to assume it's the former. If it's the latter, just switch everything I say.
Now you want to test if B has better consumption. So you want to see if mean of A < mean of B. (I will write this as ua <ub.
So your hypothesis would be
Ho: ua - ub = 0
H1: ua < ub or ua - ub < 0
I'm assuming the sd's are the sample sd. If so, plug in all the info into the t test formula.
It should be something like [(x1-x2) - (u1-u2)]/sqrt(s1^2/n1 + s2^2/n2)
You have all the info provide. x1=13.04 s1^2=4^16 n1=239 u1-u2=0
You will now have your t score.
Figure out the degrees of freedom. It's either going to be n1+n2 - 2 or some weird long formula. I dont remember which one it was exactly. You should be able to find it in your book.
Now you should know that this is a one tailed (left) test because of the < in the h1.
Go to your t chart and figure out the p value.
If your sd's were population sds, then you would do the same thing, but use the z test and the z chart.
how do you volunteer to let union workers work on your house?
pynk_devil
i want to find out how to go about get on a list to have my heating and ventilation unit installed if thats possible.
kind of like when you take ur car to the community colleges trade school to get work on.
not sure who to call or where to look for information i tried tryping in hvac unions on the net local and web but i havent found any info
Answer
There are many unions that represent the HVAC/R trade although there are 2 that represent the majority of union HVAC/R shops. They are the International Union of Operating Engineers (IUOE) and The United Association of Plumbers and Pipefitters (UA). I was a proud member of the IUOE Local 1 and am now a Proud member of the Pipefitters Local Union 208. I know that both of these locals are very commited to community service. Without knowing where you are in the country I can't tell you which local to contact but either organization should be easy to look up now that you know the names. Thank you for supporting your local union.
There are many unions that represent the HVAC/R trade although there are 2 that represent the majority of union HVAC/R shops. They are the International Union of Operating Engineers (IUOE) and The United Association of Plumbers and Pipefitters (UA). I was a proud member of the IUOE Local 1 and am now a Proud member of the Pipefitters Local Union 208. I know that both of these locals are very commited to community service. Without knowing where you are in the country I can't tell you which local to contact but either organization should be easy to look up now that you know the names. Thank you for supporting your local union.
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