Classify each variable in this data table as categorical or numeric (otherwise called continuous).
Column name and description
- ID: participant identification number
- Sex: Gender coded 1=male, 2=female
- Age group: Age coded as 1=15 to 17 years; 2=18 to 29 years; 3=30 to 64 year;, 4=65 or more years
- Activities: Respondents answer to the question: “How many activities did you attend this week which required you to leave your house? Include sporting, cultural, social and community activities”.
- Transport: Most commonly used transport to attend these activities coded 1=drive car/ride motorcycle, 2=passenger in car or motorcycle, 3=public transport, 4=other
Excerpt from the data set:
| ID | Sex
(1=male, 2=female) | Age group
(1=15 to 17 years, 2=18 to 29 years, 3=30 to 64 years, 4=65 or more years) | Number of activities attended this week | Most commonly used transport
(1=drive car/ride motorcycle, 2=passenger in car or motorcycle, 3=public transport,
4=other) |
| 1 | 1 | 1 | 1 | 1 |
| 2 | 1 | 2 | 2 | 2 |
| 3 | 2 | 3 | 3 | 3 |
| 4 | 2 | 4 | 4 | 4 |
Question 2 (3marks)Note: Each student will get different answers as the data sets differ.
a. Using the assignment data file allocated to you and R Commander, tabulate the relationship between gender (sex) and most frequently used mode of transport in the past month (transport). Please use the results from R Commander to create table in Word with appropriate headings (the output from R Commander is poorly labelled and will not be accepted). (1 mark)
b. Using row or column percentages describe the relationship between gender and most frequently used mode of transport in the past month. (2 marks)
Question 3 (7 marks)Note: Each student will get different answers as the data sets differ.
a. Using the assignment data file allocated to you and R Commander, graph the relationship between the number of activities attended in the past month (activities) and drivers licence status in this sample of 17-year-old Australians. This figure should be prepared in R Commander with appropriate axis labels then copied and pasted into your assignment answers with appropriate title. (1 mark)
b. Use appropriate statistics to describe the centre, spread and shape of the distribution of number of activities attended per month for each category of drivers licence status separately. You must clearly indicate which statistics describe the centre, which describe the spread and which describe the shape. Copying R Commander output is insufficient and should be avoided. (3 marks)
c. Using the results in parts a. and b. above, describe the relationship between number of activities attended in the past month and drivers licence status. (3 marks)
Question 4(4 marks)Note: Each student will get different answers as the data sets differ.
- Using the assignment data file allocated to you and R Commander, draw an appropriate graph of the relationship betweenself-reported sedentary hours per week and number of activities attended in the past month.When preparing the graph in R Commander don’t forget to provide meaningful labels on the axes. (1 mark)
- Using the graph on a. describe the form, direction and strength of the relationship between self-reported sedentary hours per week and number of activities attended in the past month. (3 marks)
Question 5 (3 mark)
A group of 8 students were asked about their age, gender and area of study. The responses (sorted on age) are shown in the following table:
| initials | Age in years | Gender | Area of study |
| HP | 17 | Male | Nursing |
| RT | 19 | Male | Accounting |
| SK | 20 | Female | Psychology |
| KZ | 20 | Male | Psychology |
| AN | 21 | Female | Nursing |
| KK | 22 | Female | Psychology |
| JH | 22 | Male | Psychology |
| PV | 25 | Female | Nursing |
a. If you select one person at random from this group, what is the probability this person will be 18 or more years of age? (1 mark)
b. If you selected one person at random from this group, what is the probability they will be a female who is studying psychology? (1 mark)
c. If you selected one female at random from this group, what is the probability they will be 21 or more years of age and studying nursing? (1 mark)
Question 6(3 marks)
In Australia, the probability of having blood type B is 0.1.
a. Blood type was recorded for a random sample of 250 Australian adults. Using R Commander, what is the probability that this random sample of 250 adults will contain 25 or fewer people whose blood group is B? (1 mark)
b. Suppose many random samples were drawn and each of these samples contained exactly 250 people. We would predict 12% of all samples to contain fewer than how many people with type B blood? (1 mark)
c. Estimate the mean number of people with type B blood per sample. Show any working. (1 mark)
Question7(6 marks)
The hours of sleep per night for 17 year olds is known to be Normally distributed with mean 8.2 hours and standard deviation of 0.6 hours. Usingthis information to address the following questions. Show any working.
a. In 17 year olds, how many hours sleep corresponds with a z-score of 1. (1 mark)
b. Choose one 17-year old at random from this population. Using R Commander, estimate the probability that this person sleeps between 7.5 and 8.0 hours per night? (2 marks)
c. Choose a random sample of sixteen 17-year olds. Using R Commander, estimate the probability that the sample mean for normal nights will lie between 7.5 and 8.0 hours per night?Show any working. (2 marks)
d. Choose a random sample of sixteen 17 years olds, how many of this group would you expect to sleep between 7.5 and 8.0 hours. (1 mark)