Search
Create
Log in
Sign up
Log in
Sign up
AMAT 108 Final
STUDY
Flashcards
Learn
Write
Spell
Test
PLAY
Match
Gravity
Terms in this set (51)
A magazine publisher mails a survey to every subscriber asking about the quality of its subscription service. The total number of subscribers represents what?
population
A magazine publisher mails a survey to every subscriber asking about the quality of its subscription service. Mailing a survey to every subscriber represents what?
sampling method
A magazine publisher mails a survey to every subscriber asking about the timeliness of its subscription service. The publisher finds that only 5% of the subscribers responded. This 5% represents what?
sample
A magazine publisher mails a survey to every subscriber asking about the quality of its magazine. The publisher wants 100% of the subscribers to respond. This 100% response rate will represent what?
census
A magazine publisher will mail a survey to 12% of its subscribers that will be chosen at random. The survey asks about the quality of its subscription service. All of the subscribers, who have an equal and random chance to be chosen for this survey, represent what?
sampling frame
A magazine publisher mailed a survey to all of its subscribers asking if the magazine is helpful in their daily lives. Of those who responded, 56% replied that the magazine was helpful. The proportion that replied that the magazine is helpful is known as what?
population parameter of interest
Census
an entire population
Sampling frame
the list or lists from which individuals or households are selected ex) incl all individuals in the target population; exclude all individuals not in the target population
Sampling method
the way that observations are selected from a population to be in the sample
Parameter of interest
any measure (mean, sd) that's computed for population data
Sample
consists only of observations drawn from the population; meant to be representative of the population a group of people selected from a larger group (population)
Population
any entire collection of people from which we may collect data. It's the entire group we are interested in, which we wish to describe or draw conclusions about; any complete group with at least one characteristic in common
Systematic sampling
A value k is specified (for example k = 50 or k = 200). One of the first k individuals is selected at random. Then every kth individual in the sequence is included in the sample. This method works reasonably well as long as there are no repeating patterns in the population list.
Stratified Random Sampling
Population is divided into non-overlapping subgroups called strata. Simple random samples are selected from each stratum.
In other words, separate simple random samples are independently selected from each subgroup. Ex) to estimate the average cost of malpractice insurance, a researcher might find it convenient to view the population of all doctors made up of 4 subpopulations: surgeons, family practitioners, etc, etc. Rather than taking a random simple sample from the population of all doctors, the researcher could take a 4 separate simple random samples.
Cluster Sampling
Population is divided into non-overlapping subgroups called clusters. Randomly select clusters and then all the individuals in the clusters are included in the sample.
Convenience sampling: voluntary response sampling
Rely entirely on individuals who volunteer to be a part of the sample, often by responding to an ad, calling a phone number, or logging on to Inet to complete a survey. It's extremely unlikely that individuals participating in such survey are representative of any larger population of interest.
An education researcher randomly selects 38 schools from one school district and interviews all the teachers at each of the 38 schools. Identify the type of sampling used in this example.
Cluster sampling
At a college there are 120 freshmen, 90 sophomores, 110 juniors, and 80 seniors. A school administrator selects a random sample of 12 of the freshmen, a random sample of 9 of the sophomores, a random sample of 11 of the juniors, and a random sample of 8 of the seniors. She
then interviews all the students selected. Identify the type of sampling used in this example.
Stratified sampling
A newly-premiered play just ended that evening at a local theater. Theater management briefly interviews every seventh person leaving the theater to see if that person will recommend the play at that theater to other people. Identify the type of sampling used in this example.
Systematic sampling
During the winter season, a prominent newspaper reporter is interested in writing a story about the lack of proper heating of apartment buildings in the city in which he lives. During a particular frigid weekend, this reporter manages to interview almost everyone in his own apartment building. The reporter finds that everyone, including himself, is satisfied with the heating in the apartment building. Identify the type of sampling used in this example.
Convenience sampling
At the local college a survey was being done on whether or not the students liked the cafeteria food. The survey was located in the college newspaper and was to be filled out and sent to the editing office. Identify the type of sampling used in this example.
Voluntary response sampling
Nonresponse bias
Tendency for samples to differ from the corresponding population because data are not obtained from all individuals selected for inclusion in the sample.
Measurement/response bias
When Qs on a survey are worded in a way that tends to influence the response.
Undercoverage of the population
When some groups in the population are left out of the process of choosing the sample.
Voluntary response bias
When sample members are self-selected volunteers
Inside the boxes of a new brand of cereal, is a short survey that can be mailed back for free to the manufacturer. The survey asks the consumer if he or she likes the cereal or not. What, if any, will be the most noticeable bias for this survey?
Voluntary response bias
A cereal manufacturer randomly samples households across the country by telephone. The survey asks the consumer to explain honestly in fifty words or less why he or she likes or dislikes its brand of cereals. It is also stated that for those who participate in this telephone survey, a random drawing will be held for an all-expense paid, two-week cruise. What, if any, will be the most noticeable bias for this survey?
Response bias
A newspaper reporter decided to sample residents of all major metropolitan areas in the entire country. This sampling asked if the residents liked living in their city, or are they considering moving, and if so, where? Unfortunately, this survey went over budget and was stopped, and only the east coast of the country was adequately interviewed. With regards to having this survey
labeled as representing the entire country, what, if any, will be the most noticeable bias for this survey as it is now?
Undercoverage of the population
A newspaper conducted a random telephone survey during the day regarding the percentage of stay-at-home moms and dads in the typical household. What, if any, will be the most noticeable bias for this survey?
Nonresponse bias
A newspaper reporter randomly sampled households by telephone during various times of the day. The people sampled are within the area of the newspaper's distribution. The newspaper reporter asked, "Are you patriotic in a time of war or armed conflict?" What, if any, will be the most noticeable bias for this survey?
Response bias
780 patients suffering from high blood pressure were randomly assigned to one of three groups. Over a four-month period, the first group received an experimental drug, the second group received a placebo, and the third group received no treatment. The diastolic blood pressure of each participant was measured at the beginning and at the end of the period and the change in blood pressure was recorded. The biggest decrease in blood pressure was for those who received the
drug.
Experiment
Among a group of married women who were tracked for ten years, those who worked full time were more likely to divorce than those who did not work full time. Identify the subjects studied.
Married women working full time or not
An examination of the medical records of 10, 000 women who died between 1990 and 2000 showed that those who had taken steroids had a higher risk of osteoperosis. Identify the subjects studied.
Women who died between 1990 and 2000
An examination of the medical records of 10, 000 women who died between 1990 and 2000 showed that those who had taken steroids had a higher risk of osteoperosis. Identify the parameter of interest.
Risk of osteoperosis
In a clinical trial, 780 participants suffering from high blood pressure were randomly assigned to one of three groups. Over a one-month period, the first group received a low dosage of an experimental drug, the second group received a high dosage of the drug, and the third group received a placebo. The diastolic blood pressure of each participant was measured at the beginning and at the end of the period and the change in blood pressure was recorded. The biggest decrease in blood pressure was for those who received the low dosage of the drug. Identify the response variable measured.
Change in diastolic blood pressure
780 men suffering from high blood pressure were randomly assigned to one of three groups. Over a four-month period, the first group received a low dosage of an experimental drug, the second group received a high dosage of the drug, and the third group received a placebo. The biggest decrease in blood pressure was for those who received the low dosage of the drug. Identify the subjects studied.
Men suffering from high blood pressure
780 participants suffering from depression were randomly assigned to one of three groups. Over a four-month period, the first group received a low dosage of an experimental drug, the second group received a high dosage of the drug, and the third group received a placebo. At the end of the period each participant rated their mood on a scale of 1-5. Identify the treatments.
Placebo, low dosage, high dosage
In a group of 500 women, those who smoked moderately did worse on tests of reaction time than those who did not smoke. Identify the subjects studied.
Women who smoke moderately and women who do not smoke
An education researcher was interested in examining the effect of the teaching method and the teacher on the reading level of students with learning disabilities. 257 students with learning
disabilities participated in an experiment. There are four different teachers (Juliana, Felix, Sonia, and Helen) and three different teaching methods (A, B, and C). Students are randomly assigned to a teaching method and a teacher. Those who studied with Sonia using method B achieved the highest scores on a reading test. Identify the subjects studied.
Students with learning disabilities
An education researcher was interested in examining the effect of the teaching method and the teacher on students' reading levels. 257 students participated in an experiment. There were two different teachers (Juliana and Felix) and three different teaching methods (A, B, and C). Students were randomly assigned to a teaching method and teacher. At the end of the semester the students took a reading test on which they received a score out of 20. Students who studied wth Felix using method B achieved the highest scores. Identify the factor(s) in the experiment and the number of levels for each.
Teaching method (3 levels) and teacher (2 levels)
Single blind
subjects don't know which treatment was received but the individuals measuring the response do know which treatment was received, or vice versa
Double blind
neither the subjects nor the individuals who measure the response know which treatment was received
A researcher wants to examine the effect of fertilizer and the effect of sunlight on the yield of tomatoes. She bought 60 tomato plants at a local garden store. She randomly assigned 30 tomato plants to be planted on the sunny side of the hill and 30 to be planted on the shady side. Within each group of 30 plants, she randomly assigned plants to one of three groups. The first group is grown with no fertilizer, the second group with a small amount of fertilizer, and the third group with a large amount of fertilizer. All tomato plants are planted at the same time and each plant is grown to maturity. The total weight of tomatoes obtained from each plant is recorded. The person evaluating the results does not know which tomatoes received fertilizer or which were grown on the sunny side.
Single blind
A researcher wants to investigate whether different forms of exercise can be used to help hyperactive children. A group of 90 children is divided into two groups according to age - those aged 9-12 and those aged 5-9. Within each age group the children are randomly assigned to one of three groups. The first group will just do their normal exercise. The second group will be given an additional exercise routine (moderate). The third group will be given an additional exercise routine (strenuous). At the end of a four month period parents will be asked to evaluate their children's progress.
Neither
780 men suffering from high blood pressure were randomly assigned to one of two groups. Over a four-month period, the first group received an experimental drug and the second group received a placebo. A larger decrease in diastolic blood pressure was observed for those who received the drug. The patients did not know whether they were receiving the drug or the placebo. Neither the technicians administering the treatments nor the physicians evaluating the results knew which participants had received the drug and which the placebo.
Double blind
An education researcher was interested in examining the effect of the teaching method and the teacher on students' reading levels. 257 students participated in an experiment. There were two different teachers (Juliana and Felix) and three different teaching methods (A, B, and C). Students were randomly assigned to a teaching method and teacher. At the end of the semester the students took a reading test on which they received a score out of 20. Students who studied wth Felix using method B achieved the highest scores. The person evaluating the results does not know which teacher or teaching method the students were assigned to.
Single blind
A computer network manager wants to test the reliability of some new and expensive fiber-optic Ethernet cables that the computer department just received. The computer department received 4 boxes containing 30 cables each. The manager does not have the time to test every cable in each box. The manager will choose one box at random and test 6 cables chosen randomly within that box. What is the population?
120 cables
A computer network manager wants to test the reliability of some new and expensive fiber-optic Ethernet cables that computer department just received. The computer department received 5 boxes containing 30 cables each. The manager does not have the time to test every cable in each box. The manager will choose one box at random and test 6 cables chosen randomly within that box. What is the sample?
The 6 cables chosen for testing
A computer network manager wants to test the reliability of some new and expensive fiber-optic Ethernet cables that the computer department just received. The computer department received 9 boxes containing 30 cables each. The manager does not have the time to test every cable in each box. The manager will choose one box at random and test 6 cables chosen randomly within that box. What is the sampling frame?
The one box that was chosen at random from the 9 boxes
A computer network manager wants to test the reliability of some new and expensive fiber-optic Ethernet cables that the computer department just received. The computer department received 4 boxes containing 20 cables each. The manager does not have the time to test every cable in each box. The manager will choose one box at random and test 4 cables chosen randomly within that box. What is the population parameter of interest?
The proportion of reliable cables
when sample members are self-selected volunteers, as in voluntary samples. An example would be call-in radio shows that solicit audience participation in surveys on controversial topics (abortion, affirmative action, gun control, etc.). The resulting sample tends to overrepresent individuals who have strong opinions.
Voluntary response bias
;