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100
What are the 4 types of data classification in statistics?
nominal, ordinal, interval and ratio.
100
A dice is thrown. The probability of getting 1 and 5 is
1/3
100
What graphs to use in statistics?
bar, line, histogram and pie charts
100
This statistical number is the middle number of the data set.
median
100
Find the area under the standard normal curve between Z=1.5 and Z=2.4.
.0586
200
The percent of adults who smoke, recorded every few years since 1967, suggests a negative linear association with no outliers. A line was fit to the data to model the relationship.
Write a linear equation to describe the given model.
The equation is y=-0.5x+40
200
A restaurant offers a game piece with each meal to win coupons for free food. The probability of a game piece winning is 1 out of 4 and is independent of other game pieces winning. A family orders 4 meals. Let C be the number of coupons the family wins.
What type of variable is C?
binomial
200
. Which of the following statements about confidence intervals do you believe to be true?
a)A confidence interval gives an estimated range of values which is likely to include an unknown population parameter.
b)A 95% confidence interval gives the range of values which is likely to include 95 out of a 100 sample data values. ✗
c)A 95% confidence interval is wider than a 99% confidence interval.
d)A confidence interval can be calculated using an estimate of the parameter plus a multiple of the standard deviation. If you want to increase the width of the confidence interval you should increase the sample size.
a)A confidence interval gives an estimated range of values which is likely to include an unknown population parameter.
200
Violet is taking a computer-adaptive test, where each time she answers a question correctly, the computer gives her a more difficult question. Let Q be the number of questions Violet answers correctly before she misses one.
What type of variable is Q?
Neither
200
For the following correlations (r): 0.29 -0.63 0.15 -0.34 0.04
a. Which is the strongest correlation? With correlation, remember that we can think about both strength and direction of the effect, so look at the absolute value distance.
b. Which is the weakest correlation?
Strongest is -.63.
Weakest is .04
300
Q.
What is the maximum value in this stemplot?
73
300
Which line fits the data graphed below?
A
300
What are the 2 types of data in statistics?
discrete data and continuous data.
300
Statistics is
the study and manipulation of data, including ways to gather, review, analyze, and draw conclusions from data.
300
A game of chance consists of spinning an arrow which is equally likely to come to rest pointing to one of the number 1,2,3,4,....,12 ,then the probability that it will point to an odd number is:
1/6
400
If the mean value for the weight of 25 men was calculated to be 90 kg with a standard deviation of 10 kg, what would the 95% confidence interval for the mean weight be approximately?
b)86 to 94
400
Calculate the median for this set of data
22, 32, 44, 11, 5, 28, 19, 30.
median=25
400
The Chi-square test of independence is a
statistical hypothesis test used to determine whether two categorical or nominal variables are likely to be related or not
400
Jiao works as an usher at a theater. The theater has 1000 seats that are accessed through five entrances. Each guest should use the entrance that's marked on their ticket. Jiao wants to test if the distribution of guests according to entrances matches the official distribution. He collects information about the number of guests that went through each entrance at a certain night. Here are the results:
Entrance A, B, C, D, E,
Expected 30% 30% 20%, 10%, 10%,
#ofpeople 398 202 205 87 108 1000
Jiao wants to perform a chi squared goodness-of-fit test to determine if these results suggest that the actual distribution of people doesn't match the expected distribution.
What is the expected count of guests in entrance Jiao's sample?
The expected count of guests in entrance is 300.
400
Class Boundary. definition
A point that is the left endpoint of one class interval, and the right endpoint of another class interval.
500
A psychologist thinks that meditation might be a useful tool for patients trying to lose weight. They design an experiment and recruit volunteers who are all interested in losing weight. Half of the subjects (determined at random) will attend weekly guided meditation sessions and receive access to a diet and exercise program. The other half of the subjects will just have access to the diet and exercise program.
What is the primary purpose of including a group who doesn't attend meditation sessions?
To serve as a control group for comparison
500
An engineer measured the Brinell hardness of 25 pieces of ductile iron that were subcritically annealed. The resulting data were:
An engineer measured the Brinell hardness of 25 pieces of ductile iron that were sub critically annealed. The resulting data were:
170 167 174 179 179 187 179 183 179 156 163 156 187 156 167 156 174 170 183 179 174 179 170 159 187
the engineer fails to reject the null hypothesis.
500
Alex took a test in physics and scored a 35. The class average was 27 and the standard deviation was 5.
Noah took a chemistry test and scored an 82. The class average was 70 and the standard deviation was 8.
Show that Alex had the better performance by calculating -
1) Alex's standard normal percentile and
2) Noah's standard normal percentile
Alex = .945
Noah = .933
500
Which set of data has a higher mean?
BOB: 1.3, 3.1, 4.1, 2.5, 2.2, 2.8
MEGAN: 5.5, 1.1, 1.2, 2.4, 3.8, 2.0, 1.9
BOB > MEGAN
500
Rita teaches environmental biology. She has 2 forms of a midterm exam, and she wonders if either form is harder than the other. She teaches approximately 200 total students in 4 sections of the class. She randomly assigns half of the students in each section to each form of the exam. Rita will then see if the average scores are significantly different between each form.
What type of experiment design is this?
A randomized block design where the 4 sections are the blocks