my research
Exercise 1 (10 points)
Twenty-five randomly selected students were asked the number of movies they watched the previous week. The results are as follows:
# of movies Frequency
Relative Frequency
Cumulative Relative Frequency
0
5 0.2
0.2=0.2
1
9
0.36
0.2+0.36=0.56
2
6
0.24
0.56+0.24=0.8
3
4
0.16
0.8+0.16=0.96
4
1
0.04
0.96+0.04=1
Table 1.1 (Hint: This is a frequency table. Read the section in the textbook!)
a. Find the sample mean x
ANSWER = 1.48
b. Find the sample standard deviation, s ANSWER S=1.12
c. Complete the columns of the chart.
#of movies
Bin
Frequency
Cumulative %
0
0
1
20.00%
1
2
2
60.00%
2
More
2
100.00%
3
4
d. Find the first quartile.
ANSWER =1
e. Find the median.
ANSWER =1
f. Find the third quartile.
ANSWER =2
g. What percent of the students saw fewer than three movies?
20/100 =20%
h. Find the 40th percentile.
ANSWER =1
i. Find the 90th percentile.
ANSWER =2
Exercise 2 (5 points)
I. A “random survey” was conducted of 3274 people of the “microprocessor generation” (people born since 1971, the year the microprocessor was invented). It was reported that 48% of those individuals surveyed stated that if they had $2000 to spend, they would use it for computer equipment. Also, 66% of those surveyed considered themselves relatively savvy computer users. (Source: San Jose Mercury News)
a. Do you consider the sample size large enough for a study of this type? Why or why not?
ANSWER
Yes. This is a large size and larger the sample size, the more accurate the data will be when considering how a population will respond. The survey includes two categories; another reason to make the data analyst significant. The sample increases with the population size. The sample of people chosen has the same characteristics of the population the random survey is representing. The larger the random sample of a relevant population, the smaller the confidence
Twenty-five randomly selected students were asked the number of movies they watched the previous week. The results are as follows:
# of movies Frequency
Relative Frequency
Cumulative Relative Frequency
0
5 0.2
0.2=0.2
1
9
0.36
0.2+0.36=0.56
2
6
0.24
0.56+0.24=0.8
3
4
0.16
0.8+0.16=0.96
4
1
0.04
0.96+0.04=1
Table 1.1 (Hint: This is a frequency table. Read the section in the textbook!)
a. Find the sample mean x
ANSWER = 1.48
b. Find the sample standard deviation, s ANSWER S=1.12
c. Complete the columns of the chart.
#of movies
Bin
Frequency
Cumulative %
0
0
1
20.00%
1
2
2
60.00%
2
More
2
100.00%
3
4
d. Find the first quartile.
ANSWER =1
e. Find the median.
ANSWER =1
f. Find the third quartile.
ANSWER =2
g. What percent of the students saw fewer than three movies?
20/100 =20%
h. Find the 40th percentile.
ANSWER =1
i. Find the 90th percentile.
ANSWER =2
Exercise 2 (5 points)
I. A “random survey” was conducted of 3274 people of the “microprocessor generation” (people born since 1971, the year the microprocessor was invented). It was reported that 48% of those individuals surveyed stated that if they had $2000 to spend, they would use it for computer equipment. Also, 66% of those surveyed considered themselves relatively savvy computer users. (Source: San Jose Mercury News)
a. Do you consider the sample size large enough for a study of this type? Why or why not?
ANSWER
Yes. This is a large size and larger the sample size, the more accurate the data will be when considering how a population will respond. The survey includes two categories; another reason to make the data analyst significant. The sample increases with the population size. The sample of people chosen has the same characteristics of the population the random survey is representing. The larger the random sample of a relevant population, the smaller the confidence