Assignment Questions:

1. Prepare the following questionnaire in SPSS, so that its data can be stored.

2. The following information is held in a customer database.

Name, age, gender, address, height, number of email addresses provided, price quoted What is the type of each variable?

3. The following measurements were recorded for the drying time, in hours, of a certain brand of latex paint.

4.8     2.5     4.8     2.9     2.8

3.6     3.3     5.6     3.7     2.8

4.0     4.4     5.2     3.4     3.0

Assume that the measurements are a simple random sample.

(a) What is the sample size for the above sample?

(b) Calculate the sample mean for these data.

(c) Calculate the sample median.

(d) What feature in this data set is responsible for the substantial difference between the two (i.e., mean and median)?

4. Describe two ways to deal with missing data values in data for processing it.

5. A set of students were asked which sports they played during their university. They were given the following options: Netball, Swimming, Tennis or None.

Here is a list of sports they played:

Draw a Venn diagram to show this information.

6 (a). Find the errors in each of the following statements:

(i) The probabilities that an automobile salesperson will sell 0, 1, 2, or 3 cars on any given day in a month are, respectively, 0.18, 0.39, 0.30, and 0.13. (2)

(ii) The probability that it will rain tomorrow is 0.41, and the probability that it will not rain tomorrow is 0.53.

(iii) The probabilities that a printer will make 0, 1, 2, 3, or 4 or more mistakes in setting a document are, respectively, 0.18, 0.39, -0.29, 0.49, and 0.30

6 (b). Which of the following represents a valid probability table and why?

The best answer is: (a) (i)     (b) (ii)     (c) (i) and (ii)     (d) Not enough information

6 (c). In 3 tosses of a coin which of following equals the event “exactly two heads”?

A = {THH, HTH, HHT, HHH}

B = {THH, HTH, HHT}

C = {HTH, THH}

The best answer is: (a) A     (b) B     (c) C     (d) B and C

7. The probability that a certain kind of component will survive a shock test is 3/4. Find the probability that exactly 2 of the next 4 components tested survive. These tests are independent.

8. A real estate agent claims that 65% of all private residences being built today are 2- bedroom homes. To test this claim, a large sample of new residences is inspected; the proportion of these homes with 2 bedrooms is recorded and used as the test statistic. State the null and alternative hypotheses to be used in this test and determine the location of the critical region.

9. A study was made on the amount of converted sugar in a certain process at various temperatures. The data were coded and recorded as follows:

(a) Estimate the linear regression line to provide a chart and summary statistics together with the coefficients.

(b) Estimate the mean amount of converted sugar produced when the coded temperature is 1.56.

10. Below are given the 16 students’ marks of their two modules Statistics and Programming, you are required to cluster the students into three clusters.