Make Points
Determine whether the underlined value is a parameter or a statistic. Batting Average. Ty Cobbs is one of Major League Baseball's greatest hitters of all time, with a career batting average of 0.366.
The underlined value is a parameter.
Determine the level of measurement.
The day of the month.
a. Nominal
b. Ratio
c. Ordinal
d. Interval
Interval
When taking a systematic random sample of size n, every group of size n from the population has the same chance of being selected.
True or False
False
Quantitative variables classify individuals in a sample according to
a. numerical measure.
b. physical attribute.
c. personality characteristic.
d. exhibited trait.
numerical measure.
Which of the following is not true of statistics?
a. Statistics is used to answer questions with 100% certainty.
b. Statistics involves collecting and summarizing data.
c. Statistics can be used to organize and analyze information.
d. Statistics is about providing a measure of confidence in any conclusions
Statistics is used to answer questions with 100% certainty.
Determine the level of measurement.
Ranking (first place, second place, etc.) of contestants in a singing competition
a. Nominal
b. Ratio
c. Ordinal
d. Interval
Ordinal
Of the two statements, which one is qualitative/quantitative?
Statement 1: Student ID numbers.
Statement 2: Number of unpopped kernels in a bag of microwave popcorn.
Statement 1 is qualitative.
Statement 2 is quantitative.
The government of a town needs to determine if the city's residents will support the construction of a new town hall. The government decides to conduct a survey of a sample of the city's residents. Which one of the following procedures would be least appropriate for obtaining a sample of the town's residents?
a. Survey a random sample of employees at the old city hall.
b. Survey every 8th person who walks into city hall on a given day.
c. Survey the first 300 people listed in the town's telephone directory.
d. Survey a random sample of persons within each geographic region of the city.
Survey the first 300 people listed in the town's telephone directory.
Identify the type of sampling used. To estimate the percentage of defects in a recent manufacturing batch, a quality-control manager at Intel selects every 8th chip that comes off the assembly line starting with the 3rd until she obtains a sample of 140 chips.
a. The sampling being used is qualitative.
b. The sampling being used is systematic.
c. The sampling being used is clustered.
d. The sampling being used is quantitative.
The sampling being used is systematic.
A ________ is an explanatory variable that was not considered in a study, but that affects the value of the response variable in the study.
Lurking Variable
The number of violent crimes committed in a city on a given day in a random sample of 50 days is a __________ random variable.
a. Continuous
b. Discrete
Discrete
Take half of each group's total points and award none in return.
Time to pay your taxes!!
A survey of 1,805 American households found that 71% of the households own a DVD recorder. Identify the population, the sample, and the individuals in the study.
population: collection of all American households; sample: collection of 1,805 American households surveyed; individuals: each household
Which of the following is not true about factors?
a. Factors whose effect on the response variable interests us should be set at predetermined levels.
b. One way to control factors is to fix their level at one predetermined value throughout the experiment.
c. Any combination of the values of the factors is called a treatment.
d. Factors whose effect on the response variable is not of interest can be set after the experiment.
Factors whose effect on the response variable is not of interest can be set after the experiment.
Determine the level of measurement.
The musical instrument played by a music student
a. Nominal
b. Ratio
c. Ordinal
d. Interval
Nominal
A researcher wants to study the effects of advertising of accessible online college upon high school boys and sampled small Midwestern towns. The results from this study were used to project a national campaign on accessible forms of online college. What type or error may have occurred?
a. Sampling error
b. Data-entry error
c. Question error
d. Nonsampling error
Sampling Error
A researcher wanted to determine whether women with children are more likely to develop anxiety disorders than women without children. She selected a sample of 900 twenty-year old women and followed them for a twenty-year period. At the start of the study, none of the women had children. By the end of the study 53% of the women had at least one child. The level of anxiety of each participant was evaluated at the beginning and at the end of the study and the increase (or decrease) in anxiety was recorded. The researchers analyzed the results to determine whether there was an association between anxiety and having children.
a. case-control; Individuals are asked to look back in time.
b. cross-sectional; Information is collected at a specific point in time.
c. cohort; Individuals are observed over a long period of time.
cohort; Individuals are observed over a long period of time.
What is the difference between an explanatory variable and a response variable?
Explanatory - what is being put in
Response - what is being given out
Which type of bias occurs because the individuals tend to favor one part of the population over another?
a. Response bias
b. Nonresponse bias
c. Sampling bias
d. No bias
Sampling Bias
Based on 9,000 responses from 44,500 questionnaires sent to all its members, a major medical association estimated that the annual salary of its members was $122,500 per year. What sampling technique was used?
a. Stratified
b. Cluster
c. Convenience
d. Systematic
e. Simple Random
Simple Random
You Get 500!
You Get 500!
You Get 500!
Or whatever Oprah said during her give away.
In a survey conducted in the town of Atherton, 23% of adult respondents reported that they had been involved in at least one car accident in the past ten years. This is called what?
a. Parameter
b. Statistic
Statistic
A medical researcher obtains a sample of adults suffering from diabetes. She randomly assigned 42 people to a treatment group and 42 to a placebo group. The treatment group receives a medication over a period of three months and the placebo group receives a placebo over the same time frame. At the end of three months, the patient's symptoms are evaluated.
a. Observational Study
b. Experiment
Experiment
Name all four types of Sampling.
Stratified, Systematic, Cluster, and Convenience
Grouping together similar experimental units and then randomly assigning the experimental units within each group to a treatment is called ________.
blocking