STA2300: Koalas In The Wild Who Are Juveniles - Statistics Assignment

Assignment Task :

Statistics Assignment:

1) Researchers are concerned with the decline in the proportion of koalas in the wild who are juveniles, as this will impact the future adult koala population. Historically, the proportion of koalas in South East Queensland who are juveniles is 20%. a) Using SPSS, calculate the proportion of koalas in the study who are juveniles. b) Without using SPSS, determine whether there is evidence to support the theory that the proportion of koalas who are juveniles is less than 20%. Perform a hypothesis test to statistically justify your answer by completing the following: i. State the appropriate hypotheses (define any symbols used). ii. Check the conditions and assumptions for this test. iii. Calculate the test statistic for this test. iv. Calculate the P-value for this test. v. Interpret the P-value and write a meaningful conclusion in the context of this situation. 2) Use the information in the dataset koalas17.sav to answer the following questions. You should use SPSS to calculate the sample statistics you will need to do this question, but for parts (b) and (c) you are required to do all other calculations by hand, using a calculator. a) Check the appropriate conditions and assumptions needed to calculate either a confidence interval or hypothesis test in relation to the population mean height of the trees in which juvenile koalas are sighted in South East Queensland. Comment on what these checks indicate about the appropriateness of proceeding with the analysis. b) From historical data, it is known that the mean height of trees in which juvenile koalas have been sighted is 15 metres. Perform a hypothesis test to see if there is evidence to support a suspicion that the mean height of trees in which juvenile koalas are sighted in South East Queensland is more than this. 3) Use the information in the dataset koalas17.sav to answer the following questions. You should use SPSS to calculate any sample statistics you will need to do this question, but for parts b(ii) and (c) you are required to do all other calculations by hand, using a calculator. Koalas of two broad age groups were sighted in South East Queensland – adult and juvenile. As a researcher, you are interested to see whether there is a difference in the mean height of trees in which these two groups of koalas are sighted. Regardless of your answer to part a) Check the appropriate conditions and assumptions needed to perform a hypothesis test comparing the population mean heights of trees in which the two groups of koalas, based on age, are sighted. Comment on what these checks indicate about the appropriateness of proceeding with the analysis. b) Using an appropriate statistical test, determine if, on average, there is a difference in the height of trees in which the two groups of koalas, based on age, are sighted in South East Queensland. In performing the test, include: i. State appropriate hypotheses, clearly defining all symbols. ii. Calculate a suitable test statistic (you can use the results from part (a) in this calculation. iii. Find the P-value of the test (and include the degrees of freedom). iv. Interpret the P-value and write a meaningful conclusion in the context of the question. v. Now use SPSS to check your results for this hypothesis test. Attach or copy and paste the relevant output from SPSS for this test to your assignment. vi. Briefly comment on how the test statistic and P-value from SPSS output are similar to or differ from your hand calculations. c) Estimate, with 90% confidence, the population mean difference in height of trees in which the two groups of koalas, based on age, are sighted in South East Queensland. Ensure you explain the confidence interval in the context of the question. 4) Researchers have theorized that juvenile koalas, when feeding, move down the tree rather than up. In order to test this theory, the height from the ground at which each juvenile koala was located sleeping within a tree was initially measured when the koala was sighted (positionintree) and then again three hours later (laterpositionintree). It now needs to be determined whether, on average, the height of the juvenile koalas in the trees has decreased after three hours. i. State appropriate hypotheses (define any symbols used). ii. State (but do not check) the assumptions for carrying out this test. Describe the assumptions in the context of this question. iii. Calculate the value of a suitable test statistic for this test. iv. Calculate the P-value of this test. v. Interpret the P-value and describe the outcome of the test in the context of this question.

This Statistics Assignment has been solved by our Experts at My Uni Paper. Our Assignment Writing Experts are efficient to provide a fresh solution to this question. We are serving more than 10000+ Students in Australia, UK & US by helping them to score HD in their academics. Our Experts are well trained to follow all marking rubrics & referencing style.

Be it a used or new solution, the quality of the work submitted by our assignment experts remains unhampered. You may continue to expect the same or even better quality with the used and new assignment solution files respectively. There’s one thing to be noticed that you could choose one between the two and acquire an HD either way. You could choose a new assignment solution file to get yourself an exclusive, plagiarism (with free Turnitin file), expert quality assignment or order an old solution file that was considered worthy of the highest distinction.