CALCULATE➕➗✖️
Scores on a history test have an average of 80 with a standard deviation of 6. What is the z-score for a student who earned a 75 on the test?
HINT; 75-80/6
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-0.83
In a study about social media usage, if researchers only collect data from users of one specific platform, which bias is most likely present?
a) Time bias
b) Selection bias
c) Location bias
d) Day of the week bias
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B.) SELECTION BIAS
What percent of data on a bell-curve represent one standard deviation below the mean and one standard deviation below the mean?
68%
the age of a few randomly selected participants in a study about a race of runners.
POPULATION or SAMPLE?
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Sample
The colors of automobiles on a used car lot.
QUALTITATIVE or QUANTITATIVE DATA/
Qualitative
A particular leg bone for dinosaur fossils has a mean length 60 inches and with a standard deviation of 3 inches. What is the z-score that corresponds to a length of 62 inches?
0.66 or 0.67
A study on sleep patterns that only includes data from people living in urban areas might suffer from:
a) Restaurant goer bias
b) Day of the week bias
c) Location bias
d) Time bias
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C.)LOCATION BIAS
What percent of data on a bell-curve represent two standard deviations below the mean and two standard deviation below the mean?
95%
the annual salary of each full-time teacher in a study about Phoenix High School.
POPULATION or SAMPLE?
Population
sampling involves selecting participants who are easily accessible or readily available to the researcher.
Convenience Sample
A data set has a normal distribution with a mean of 53 and a standard deviation of 1. About what percent of the data are 52 or less?
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-1
If a researcher conducting interviews about political opinions unintentionally shows approval for certain responses through facial expressions, this could lead to:
a) Recall bias
b) Observer bias
c) Time bias
d) Sampling bias
B.)OBSERVER BIAS
What percent of data on a bell-curve represents three standard deviations below the mean and three standard deviations below the mean?
99.7%
A population is divided into at least two
groups, then some members (but not all) are randomly selected from each group. What type of sample is this?
Stratified Sample
Willie conducts an experiment to test if playing music affects pepper growth. He plays classical music for one group of plants and no music for another. The plants with music grow faster, but Willie later realizes these plants are closer to a heat lamp.
What is the confounding variable?
Heat Lamp
For all the students in a high school, the mean grade point average is 2.95. Is the mean grade point average a parameter or a statistic?
Statistic
Which bias might affect a study on traffic patterns if data is only collected on weekdays?
a) Time bias
b) Location bias
c) Day of the week bias
d) Observer bias
C.)DAY OF THE WEEK BIAS
What percent of data on a bell-curve represent one standard deviation below the mean and three standard deviations below the mean?
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83.64
The population is ordered in some way and every nth member is chosen.
Systematic Sample
Willie experiments with different watering frequencies and notices plants watered twice daily grow faster than those watered once. What factor may be causing faster growth in one set of plants?
They are watered more frequently.
Determine whether the study is a randomized comparative experiment.
To test a new drug for treating an ailment, a pharmaceutical company randomly divided 200 adult volunteers into two groups.
One group received the drug and one group received a placebo. After one month, the adults who took the drug were 27% less likely to experience symptoms, while those who took the placebo experienced no significant change.
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Yes
When a study inadvertently excludes certain groups of people, this is most likely:
a) Sampling bias
b) Day of the week bias
c) Restaurant goer bias
d) Recall bias
A.)SAMPLING BIAS
What percent of data on a bell-curve represent three standard deviations below the mean and two standard deviations above the mean?
95%
You want to know the g-forces a person would experience during a fall from a 90 foot high bridge into a lake.
What type of experiment must you conduct?
Simulation
A researcher asks 35 people whether they have visited Arkansas.
Identify the method used:
a.)observational study
b.)survey
c.)experiment
Survey