Approximately 86.5% of Americans commute to work by car, truck, or van. Out of that group, 84.6% drive alone and 15.4% drive in a carpool. Approximately 3.9% walk to work and approximately 5.3% take public transportation.
Construct a table or a tree diagram of the situation. Include a branch for all other modes of transportation to work.
Assuming that the walkers walk alone, what percent of all commuters travel alone to work?
Suppose that 1,000 workers are randomly selected. How many would you expect to travel alone to work?
Suppose that 1,000 workers are randomly selected. How many would you expect to drive in a carpool?
Car, Truck or Van
Walk
Public Transportation
Other
Totals
Alone
0.7318
Not Alone
0.1332
Totals
0.8650
0.0390
0.0530
0.0430
1
If we assume that all walkers are alone and that none from the other two groups travel alone (which is a big assumption) we have:
P (Alone) = 0.7318 + 0.0390 = 0.7708.
Make the same assumptions as in (b) we have: (0.7708)(1,000) = 771
When the Euro coin was introduced in 2002, two math professors had their statistics students test whether the Belgian one Euro coin was a fair coin. They spun the coin rather than tossing it and found that out of 250 spins, 140 showed a head (event
H ) while 110 showed a tail (event
T ). On that basis, they claimed that it is not a fair coin.
Based on the given data, find
P (
H ) and
P (
T ).
Use a tree to find the probabilities of each possible outcome for the experiment of tossing the coin twice.
Use the tree to find the probability of obtaining exactly one head in two tosses of the coin.
Use the tree to find the probability of obtaining at least one head.
Use the following information to answer the next two exercises. The following are real data from Santa Clara County, CA. As of a certain time, there had been a total of 3,059 documented cases of AIDS in the county. They were grouped into the following categories:
* includes homosexual/bisexual IV drug users
Homosexual/Bisexual
IV Drug User*
Heterosexual Contact
Other
Totals
Female
0
70
136
49
____
Male
2,146
463
60
135
____
Totals
____
____
____
____
____
Suppose a person with AIDS in Santa Clara County is randomly selected.
Find
P (Person is female).
Find
P (Person has a risk factor heterosexual contact).
Find
P (Person is female OR has a risk factor of IV drug user).
Find
P (Person is female AND has a risk factor of homosexual/bisexual).
Find
P (Person is male AND has a risk factor of IV drug user).
Find
P (Person is female GIVEN person got the disease from heterosexual contact).
Construct a Venn diagram. Make one group females and the other group heterosexual contact.
Answer these questions using probability rules. Do NOT use the contingency table. Three thousand fifty-nine cases of AIDS had been reported in Santa Clara County, CA, through a certain date. Those cases will be our population. Of those cases, 6.4% obtained the disease through heterosexual contact and 7.4% are female. Out of the females with the disease, 53.3% got the disease from heterosexual contact.
Find
P (Person is female).
Find
P (Person obtained the disease through heterosexual contact).
Find
P (Person is female GIVEN person got the disease from heterosexual contact)
Construct a Venn diagram representing this situation. Make one group females and the other group heterosexual contact. Fill in all values as probabilities.
sorry question a bit unclear...do you mean how do you analyze quantitative data? If yes, it depends on the specific question(s) you set in the beginning as well as on the data you collected. So the method of data analysis will be dependent on the data collecter and questions asked.
Bheka
how to solve for degree of freedom
saliou
Quantitative data is the data in numeric form. For eg: Income of persons asked is 10,000. This data is quantitative data on the other hand data collected for either make or female is qualitative data.
Rohan
*male
Rohan
Degree of freedom is the unconditionality. For example if you have total number of observations n, and you have to calculate variance, obviously you will need mean for that. Here mean is a condition, without which you cannot calculate variance. Therefore degree of freedom for variance will be n-1.
Rohan
data that is best presented in categories like haircolor, food taste (good, bad, fair, terrible) constitutes qualitative data
Bheka
vegetation types (grasslands, forests etc) qualitative data
Bheka
I don't understand how you solved it can you teach me
how we make a classes of this(170.3,173.9,171.3,182.3,177.3,178.3,174.175.3)
Sarbaz
6.5
phoenix
11
Shakir
7.5
Ron
why is always lower class bundry used
Caleb
Assume you are in a class where quizzes are 20% of your grade, homework is 20%, exam _1 is 15%,exam _2 is 15%, and the final exam is 20%.Suppose you are in the fifth week and you just found out that you scored a 58/63 on the fist exam. You also know that you received 6/9,8/10,9/9 on the first
You have to plot the class midpoint and the frequency
Wydny
ok so you use those two to draw the histogram right.
Amford
yes
Wydny
ok can i be a friend so you can be teaching me small small
Amford
how do you calculate cost effectiveness?
George
Hi everyone, this is a very good statistical group and am glad to be part of it. I'm just not sure how did I end up here cos this discussion just popes on my screen so if I wanna ask something in the future, how will I find you?
Bheka
To make a histogram, follow these steps:
On the vertical axis, place frequencies. Label this axis "Frequency".
On the horizontal axis, place the lower value of each interval. ...
Draw a bar extending from the lower value of each interval to the lower value of the next interval.
I want to test linear regression data such as maintenance fees vs house size. Can I use R square, F test to test the relationship?
Is the good condition of R square greater than 0.5
@Nistha Kashyap Random sampling is the selection of random items (or random numbers) from the group.
A sample error occurs when the selected samples do not truely represent the whole group. The can happen when most or all of the selected samples are taken from only one section of the group;
Not difference in the formula except the notation, sample mean is denoted by x bar and population mean is denoted by mu symbol.
There is formula as well as notation between difference variance and standard deviations
Akash
Likely the difference would be in the result, unless the sample is an exact representation of the population (which is unlikely.)
Ron
what is data
Nii
Nii Avin - Data is just a simple way to refer to the numbers in the population, or in the sample used in your calculations.
Ron
what are the types of data
Nii
Data is the very pale android from the Star Trek Enterprise
Andrew
Am Emmanuel from Nigeria
Emmanuel
Am Qudus from Nigeria
Rasak
am Handson from Cameroon
Handson
what is a mode?
Handson
Nii - data is whatever you are sampling. Such as the number of students in each classroom.
Ron
Handson Ndintek - the mode is the number appearing most frequently. Example: 7 9 11 7 4 6 3 7 2. 7 is the mode. In a group such as 7 9 1 4 6 3, there is no mode because no number appears more often than any other.