Assignment -1 10 Marks :

Last date for submission (in Portal) : 30th Oct. 2015

Student name: Senan Humaid Senan Saeed Al Mansoori

Student id s20131134

1-discuss the differences between statistics as numerical facts and statistics as a discipline of field of

study.

Answer

Statistics as a numerical fact is a piece of numerical information, also known as data, used to describe an

event, occurrence or phenomena. Statistics as a discipline uses statistics or numerical pieces of

information to solve problems in the everyday world and in academics. Those who work with statistics as

a discipline are called statisticians.

The discipline of statistics covers several areas of science and industries, including the environment,

health and epidemiology, computer science and astronomy. Statisticians may also work in education,

engineering and in other non-science sectors such as business. Work is done primarily in an office setting,

but they may also travel to sites to collect data to analyze later.

Statisticians may work for government or in the private sector. Statistician positions generally require a

graduate degree in mathematics or statistics, but some jobs may only require a bachelor's degree.

Statisticians present their data through several graphs and plots such as pie or chart graphs, bar graphs

and stem and leaf plots.

Statistics may be descriptive or inferential. Descriptive statistics describe features of the population or

sample being studied and includes measurements such as mean, median and mode. Inferential statistics

involve inferring something about the population studied. This process is done through hypothesis

testing.

1- the U.S departments of energy provides fuel economy information

Answer

a. How many elements are in this data set?

Answer: There are 10 elements or observations in this data set.

b. How many variables are in this data set? Answer: There are 5

variables in this data set, Class, Cylinders, City MPG, Highway MPG,

and Fuel Type.

c. Which variables are categorical and which are quantitative? Answer:

Class and Fuel Type are Categorical, Cylinders, City MPG and Highway

MPG are quantitative.

d. What type of measurement scale is used for each of the variables?

Answer: Class and Fuel Type are nominal. Cylinders, City MPG and

Highway MPG are Ratio.

3 refer back to Table 1.6 a. What is the average fuel efficiency rating for

city driving? Answer: The average city gas mileage is 182/10 = 18.2

mpg.

b. On average, how much higher is the fuel efficiency rating for highway

driving as compared to city driving? Answer: The average gas mileage

for highway travel is 261/10 = 26.1 mpg. So, on average the average

mileage for highway travel 7.9 mpg higher than city driving.

c. What percentage of the cars have four-cylinder engines? Answer:

Three of the 10 cars have 4 cylinders, so 30 percent are four cylinders.

d. What percentage of the cars will run on regular fuel? Answer: Seven

of the 10 cars run on regular fuel, so 70 percent run on regular fuel.

15.A doctor 's office staff student the waiting times for patttents who arrive at the office with a

request

2-

Answer

A doctor's office staff studied the waiting times for patients who arrive at the office

with a request for emergency service. The following data with waiting times in

minutes were collected over a one-month period.

4 7 13 12 5 5 7 15 13 7 5 7 12 23 5 7 7 11 16 1

1. Fill in the frequency (0 decimals) and the relative frequency (2 decimals) values

below.

Waiting Time Frequency Relative Frequency

0-4 2

0.1

5-9 10

0.5

10-14 5

0.25

15-19 2

0.1

20-24 1

0.05

(Total) 20

1

2.

3. Fill in the cumulative frequency (0 decimals) and the cumulative relative frequency

(2 decimals) values below.

Waiting Time Cumulative Frequency Cumulative Relative Frequency

Less than or equal to 4 2

Less than or equal to 9 12

Less than or equal to 14 17

Less than or equal to 19 19

Less than or equal to 24 20

4. What proportion of patients needing emergency service wait 9 minutes or less?

10 patients