# Statistics questions help - IMPORTANT ASAP (1 Viewer)

#### mgg20

##### New Member
Hi, is anyone able to help with the following questions? I'm very confused and my assessment is due in a few days. I have done majority of the questions, i just dont know these ones

Q1 - In a study of 180 participants with Carpal tunnel syndrome, half had surgery and the other half had a splint. in the surgery group, 65 patients showed improvements after 3 months while 42 of those who used a wrist split improved.
Is surgery more effective than the use of wrist splints for patients with this condition?

a) write appropriate hypothesis.
b) test the hypothesis, find the P-value and state your conclusion in plain English. use a = 0.01.
c) create a 98% confidence interval for the different proportion of patients showing improvement, and interpret your interval.
d) comment on your interval in relation to b).

Q3 - what is the effect of concussion on brain size? researchers measured the brain sizes (hippocampal volume in microlitres) of 25 football players with a history of medically diagnosed concussion and 25 football players who did not have any history of concussions.
The data are summarized below:

 GROUP MEAN ST. DEVIATION Concussion 5819 597.2 Non-concussion 6377 709.8
a) are the mean brain sizes for footballers from the two concussion groups significantly different? carry out a hypothesis test. use a significance level of 5% and use df = n1+n2 - 2.
b) create a 95% confidence interval for the mean difference in brain size, and interpret the interval.

Q4 - manufacturers of genetic drug brands must show that they do not differ significantly from the reference drugs that they imitate. once aspect in which drugs might differ is their extent of absorption in the blood. ten randomly selected healthy adults were given each drug. the order that subjects received the drugs was randomized, with a washout period between drugs.
the amount of both drugs absorbed is shown below for each of the ten subjects.
Absorption extent:

 1 2 3 4 5 6 7 8 9 10 Reference Drug 4108 2526 2779 3852 1833 2463 2059 1709 1829 2594 Generic Drug 1755 1138 1613 2254 1310 2120 1851 1878 1682 2613
a) explain why the absorption amounts should be analysed as paired data.
b) do the drugs differ significantly in the amount of absorbed in the blood?
c) carry out a hypothesis test using a = 0.05 and write your conclusion.
d) calculate a 90% confidence interval for the difference in absorption amounts for the two drugs, and interpret the interval.
did you expect 0 to be contained in the interval? explain.

Q5 - the Australian red cross states the 38% of the population have type A blood, 10% are type B, 3% are AB and 49% have type O. A local blood bank recorded the frequencies of each blood type for 100 donors, with the results shown below.

 BLOOD TYPE NO. OF DONORS. A 42 B 7 AB 5 O 46

a) if the local blood bank donor blood types match that of the general population, what would be the expected counts for each blood type?
b) to see if these results are unusual, should you perform a goodness-of-fit test or a test of independence?
d) how many degrees of freedom are there?
e) find x2 and the p-value.
f) state your conclusion (use a=0.05) in the context of the question.

Q6 - Are crime and the relationship of the criminal to the victim independent? the following table shows data on randomly selected crimes victims.
 HOMICIDE ROBBERY ASSAULT CRIMINAL WAS A STRANGER 12 379 727 CRIMINAL WAS KNOWN THE THE VICTIM 39 106 642
a) state the null hypothesis and alternative hypothesis for this test of association/independence.
b) how many degrees of freedom are there?
c) find x2 and the p-value.
d) state your conclusion (using a = 0.05) in plain English.

Q8 - an experiment was designed to compare the lengths of time of pain relief that four different drugs provided, following surgery. 20 patients were randomly assigned to be administered one of the four drugs following surgery and the length of their pain relief was recorded. the results (in hours) are shown below.
 DRUG 1 DRUG 2 DRUG 3 DRUG 4 8 6 9 4 9 5 9 2 7 6 11 4 4 4 10 4 2 4 12 2
a) state the null and alternative hypotheses required to test if the pain relief times are significantly different between any of the drugs.
b) carry out the ANOVA, and report the test statistic and p-value.
write a brief conclusion of the ANOVA analysis.
c) write a brief conclusion of the ANOVA conclusion.
d) carry out the bonferroni's multiple comparisons and summarize the results, if appropriate.

If anyone could help out with this, it is much appreciated. I am really stuck on this and need it ASAP

#### Drdusk

##### π
Moderator
Hi, is anyone able to help with the following questions? I'm very confused and my assessment is due in a few days. I have done majority of the questions, i just dont know these ones

Q1 - In a study of 180 participants with Carpal tunnel syndrome, half had surgery and the other half had a splint. in the surgery group, 65 patients showed improvements after 3 months while 42 of those who used a wrist split improved.
Is surgery more effective than the use of wrist splints for patients with this condition?

a) write appropriate hypothesis.
b) test the hypothesis, find the P-value and state your conclusion in plain English. use a = 0.01.
c) create a 98% confidence interval for the different proportion of patients showing improvement, and interpret your interval.
d) comment on your interval in relation to b).

Q3 - what is the effect of concussion on brain size? researchers measured the brain sizes (hippocampal volume in microlitres) of 25 football players with a history of medically diagnosed concussion and 25 football players who did not have any history of concussions.
The data are summarized below:

 GROUP MEAN ST. DEVIATION Concussion 5819 597.2 Non-concussion 6377 709.8
a) are the mean brain sizes for footballers from the two concussion groups significantly different? carry out a hypothesis test. use a significance level of 5% and use df = n1+n2 - 2.

b) create a 95% confidence interval for the mean difference in brain size, and interpret the interval.

Q4 - manufacturers of genetic drug brands must show that they do not differ significantly from the reference drugs that they imitate. once aspect in which drugs might differ is their extent of absorption in the blood. ten randomly selected healthy adults were given each drug. the order that subjects received the drugs was randomized, with a washout period between drugs.
the amount of both drugs absorbed is shown below for each of the ten subjects.
Absorption extent:

 1 2 3 4 5 6 7 8 9 10 Reference Drug 4108 2526 2779 3852 1833 2463 2059 1709 1829 2594 Generic Drug 1755 1138 1613 2254 1310 2120 1851 1878 1682 2613
a) explain why the absorption amounts should be analysed as paired data.

b) do the drugs differ significantly in the amount of absorbed in the blood?
c) carry out a hypothesis test using a = 0.05 and write your conclusion.
d) calculate a 90% confidence interval for the difference in absorption amounts for the two drugs, and interpret the interval.
did you expect 0 to be contained in the interval? explain.

Q5 - the Australian red cross states the 38% of the population have type A blood, 10% are type B, 3% are AB and 49% have type O. A local blood bank recorded the frequencies of each blood type for 100 donors, with the results shown below.

 BLOOD TYPE NO. OF DONORS. A 42 B 7 AB 5 O 46
a) if the local blood bank donor blood types match that of the general population, what would be the expected counts for each blood type?

b) to see if these results are unusual, should you perform a goodness-of-fit test or a test of independence?
d) how many degrees of freedom are there?
e) find x2 and the p-value.
f) state your conclusion (use a=0.05) in the context of the question.

Q6 - Are crime and the relationship of the criminal to the victim independent? the following table shows data on randomly selected crimes victims.
 HOMICIDE ROBBERY ASSAULT CRIMINAL WAS A STRANGER 12 379 727 CRIMINAL WAS KNOWN THE THE VICTIM 39 106 642
a) state the null hypothesis and alternative hypothesis for this test of association/independence.

b) how many degrees of freedom are there?
c) find x2 and the p-value.
d) state your conclusion (using a = 0.05) in plain English.

Q8 - an experiment was designed to compare the lengths of time of pain relief that four different drugs provided, following surgery. 20 patients were randomly assigned to be administered one of the four drugs following surgery and the length of their pain relief was recorded. the results (in hours) are shown below.
 DRUG 1 DRUG 2 DRUG 3 DRUG 4 8 6 9 4 9 5 9 2 7 6 11 4 4 4 10 4 2 4 12 2
a) state the null and alternative hypotheses required to test if the pain relief times are significantly different between any of the drugs.

b) carry out the ANOVA, and report the test statistic and p-value.
write a brief conclusion of the ANOVA analysis.
c) write a brief conclusion of the ANOVA conclusion.
d) carry out the bonferroni's multiple comparisons and summarize the results, if appropriate.

If anyone could help out with this, it is much appreciated. I am really stuck on this and need it ASAP
This looks like half or more of the assignment. While we are here to help answer questions and give hints we can’t just do that much of the assignment for you. That would be cheating. After all it is your job to study the content learn it and then if you need help on something we can help you. This looks like you’ve not studied a lot of the content.

I don’t know how to do the questions either but someone here probably does.

#### Velocifire

##### Out of Order
I feel bad if you typed this up, I think 181 people now have carpal tunnel syndrome.

Probably like one question would be the limit? Like how some people just ask for help with like Question 13a from a Math Textbook on here for example?

Also don't teachers patrol the website so they could also see that you are seeking for unofficial help?

#### mgg20

##### New Member
This looks like half or more of the assignment. While we are here to help answer questions and give hints we can’t just do that much of the assignment for you. That would be cheating. After all it is your job to study the content learn it and then if you need help on something we can help you. This looks like you’ve not studied a lot of the content.

I don’t know how to do the questions either but someone here probably does.

the assignment was 20 questions and I’ve done most of them. Maths is not my strong suit and never has been no matter how much I study the content. I actually don’t have any class slides for these and the textbook is useless.
I don’t want people to answer them for me.All I need is some help on how to go about answering them or even just the equations on how to determine all of these, but not actually fill them out. So I can still fill out the assessment and have answers relevant to my situation, but just the equations themselves. If that makes sense.

#### Drdusk

##### π
Moderator
Probably like one question would be the limit? Like how some people just ask for help with like Question 13a from a Math Textbook on here for example?
There’s no limit but usually people just wanna see you’ve given it a go yourself and tried, maybe your thoughts on how to do it or your own working out so we can see what your doing wrong.

#### mgg20

##### New Member
I feel bad if you typed this up, I think 181 people now have carpal tunnel syndrome.

Probably like one question would be the limit? Like how some people just ask for help with like Question 13a from a Math Textbook on here for example?

Also don't teachers patrol the website so they could also see that you are seeking for unofficial help?
yeah my bad . Well they are actually university questions, and while this is a HSC site, I have seen some people ask uni questions on here and are the same as the questions on my assessment (not this particular one tho). So considering not everyone would have the textbook I have, that’s a little difficult.

#### mgg20

##### New Member
There’s no limit but usually people just wanna see you’ve given it a go yourself and tried, maybe your thoughts on how to do it or your own working out so we can see what your doing wrong.
also, I’m not really wanting people to do them for me. All I mean is for people to help me with the equations needed to answer the questions, if that makes sense. My textbook is useless. It really only defines each thing and not really tells you how to work them out

#### Velocifire

##### Out of Order
Oh, I feel you. Yeah, poorly written textbooks can be really bad!

I feel like I could tackle them just the words could screw me over, like with the rain one that was manageable at my current level.
Just hate words... WORDS, not my strong suit in Maths!

#### mgg20

##### New Member
Oh, I feel you. Yeah, poorly written textbooks can be really bad!

I feel like I could tackle them just the words could screw me over, like with the rain one that was manageable at my current level.
Just hate words... WORDS, not my strong suit in Maths!