Statistics Exam 1 (1,2,3)

7 September 2022
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A study is conducted to measure‚Äč children's growth rates without any treatment applied to the children. What best classifies this‚Äč study? Choose the correct answer below. Discrete data Experiment Simple random sample Observational study
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Observational study
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Which of the following is typically the least important factor to consider when conducting a statistical analysis of‚Äč data? Choose the correct answer below. Sampling method Source of the data Context of the data Formula calculation
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Formula calculation
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Fill in the blank. ‚Äč_______ is used when subjects are assigned to different groups through a process of random selection.
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Randomization
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Which of the following corresponds to the case when every sample of size n has the same chance of being‚Äč chosen? Choose the correct answer below. Simple random sample Experiment Probability sample Random sample
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simple random
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Which of the following is NOT a voluntary response‚Äč sample? Choose the correct answer below. Quiz scores from a college level statistics course are analyzed to determine student progress. A survey is taken at a mall by asking passersby if they will fill out the survey. A radio station asks for‚Äč call-in responses to a question concerning city recycling. A local dentist asks her patients to fill out a questionnaire and mail it back to determine the quality of the care received during an office visit.
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Quiz scores from a college level statistics course are analyzed to determine student progress.
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Which of the following would be classified as categorical‚Äč data? Choose the correct answer below. Hair color Your answer is correct. Number of suitcases on a plane Amount of rainfall Tree height
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Hair color
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Which level of measurement consists of categories only where data cannot be arranged in an ordering‚Äč scheme? Choose the correct answer below. Interval Ordinal Nominal Your answer is correct. Ratio
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nominal
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Which of the following is associated with a‚Äč parameter? Choose the correct answer below. Data that were obtained from a sample. Data that were obtained from an entire population. Data that were obtained from a voluntary poll at the end of a service call. A numerical measurement describing some characteristic of a sample.
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Data that were obtained from an entire population.
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What is the goal of learning‚Äč statistics? Choose the correct answer below. To accept the source of the data blindly To use statistics for deception To learn to distinguish between statistical conclusions that are likely to be valid and those that are seriously flawed To use voluntary response samples to imply results about the population
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To learn to distinguish between statistical conclusions that are likely to be valid and those that are seriously flawed
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Which of the following is NOT a level of‚Äč measurement? Choose the correct answer below. Quantitative Your answer is correct. Ratio Ordinal Nominal
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Quantitative
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Which sampling method divides the population up into‚Äč sections, randomly selects some of those‚Äč sections, then chooses all the members from the selected sections to‚Äč study? Choose the correct answer below. Convenience Cluster Stratified Systematic
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Cluster
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What does it mean for the findings of a statistical analysis of data to be statistically‚Äč significant? Choose the correct answer below. The likelihood of getting these results by chance is very small. The results are very important to the health and‚Äč well-being of a certain population. The outcome could easily occur by chance. The results do not make enough difference to be of use.
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The likelihood of getting these results by chance is very small.
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Which of the following consists of discrete‚Äč data? Choose the correct answer below. Amount of rainfall Number of suitcases on a plane Tree height Hair color
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Number of suitcases on a plane
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Fill in the blank. If we are collecting sample data for a‚Äč study, the‚Äč _______ that we choose can greatly influence the validity of our conclusions. For‚Äč example, we can use sound statistical methods to analyze data in voluntary response‚Äč samples, but the results are not necessarily valid.
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sampling method
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Survey questions may be misleading if they are‚Äč "loaded." To what does‚Äč "loaded" refer? Choose the correct answer below. Not‚Äč concise; very long drawn out questions Too much data Questions that trigger a nonresponse Intentionally worded to elicit a desired response
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Intentionally worded to elicit a desired response
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Which of the following is NOT a misuse of‚Äč statistics? Choose the correct answer below. Utilizing valid statistical methods and correct sampling techniques Misleading graphs Making conclusions about a population based on a voluntary response sample Concluding that a variable causes another variable because they have some correlation
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Utilizing valid statistical methods and correct sampling techniques
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Which sampling method subdivides the population into categories sharing similar characteristics and then selects a sample from each‚Äč subdivision? Choose the correct answer below. Convenience Systematic Cluster Stratified
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stratified
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Which of the following would be considered practically‚Äč significant? Choose the correct answer below. 8 out of 14 births resulted in male children. An average of 1.2 pounds was lost over a 12 month period using a new diet program. 1 out of 50 people were not smoking 12 months after completing a‚Äč non-smoking program. In a very large‚Äč study, it was found that Treatment I resulted in‚Äč 93% success while Treatment II resulted in‚Äč 75% success.
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In a very large‚Äč study, it was found that Treatment I resulted in‚Äč 93% success while Treatment II resulted in‚Äč 75% success.
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Which of the following would NOT cast doubt of the usefulness of sample‚Äč data? Choose the correct answer below. Nonresponse An effective sampling method Order of questions in a survey Missing data
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An effective sampling method
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A‚Äč _______ histogram has the same shape and horizontal scale as a‚Äč histogram, but the vertical scale is marked with relative frequencies instead of actual frequencies.
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relative frequency
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A‚Äč _______ helps us understand the nature of the distribution of a data set.
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frequency distribution
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In a‚Äč _______ distribution, the frequency of a class is replaced with a proportion or percent.
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relative frequency
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The bars in a histogram‚Äč _______.
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touch
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A histogram aids in analyzing the‚Äč _______ of the data.
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shape of the distribution
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Class width is found by‚Äč _______. Choose the correct answer below. subtracting the lower limit of one class from the upper limit of that same class subtracting a lower class limit from the next consecutive lower class limit subtracting the smallest value in the data set from the largest value in the data set adding the lower class limit to the upper class limit and dividing by two
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subtracting a lower class limit from the next consecutive lower class limit
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‚Äč_______ are sample values that lie very far away from the majority of the other sample values.
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outliers
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Which characteristic of data is a measure of the amount that the data values‚Äč vary? Choose the correct answer below. Center Time Distribution Variation
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variation
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‚ÄčA(n) _______ distribution has a‚Äč "bell" shape.
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normal
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The heights of the bars of a histogram correspond to‚Äč _______ values.
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frequency
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When drawings of objects are used to depict‚Äč data, false impressions can be made. These drawings are called‚Äč _______.
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pictographs
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In a‚Äč graph, if one or both axes begin at some value other than‚Äč zero, the differences are exaggerated. This bad graphing method is known as‚Äč _______.
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a nonzero axis
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A‚Äč _______ is a plot of paired data‚Äč (x,y) and is helpful in determining whether there is a relationship between the two variables.
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scatterplot
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Which of the following is a common distortion that occurs in‚Äč graphs? Choose the correct answer below. Labeling both axes Using points above the class midpoints at the heights of the class frequencies Using bars to represent the frequency of data values Using a‚Äč two-dimensional object to represent data that are‚Äč one-dimensional in nature
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Using a‚Äč two-dimensional object to represent data that are‚Äč one-dimensional in nature
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Fill in the blank. ‚ÄčA(n) _______ uses line segments to connect points located directly above class midpoint values.
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frequency polygon
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Which of the following is NOT true about statistical‚Äč graphs? Choose the correct answer below. They utilize areas or volumes for data that are‚Äč one-dimensional in nature. Similar graphs can be constructed in order to compare data sets. They can be used to consider the overall shape of the distribution. They can be used to identify extreme data values.
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They utilize areas or volumes for data that are‚Äč one-dimensional in nature.
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Why is it important to learn about bad‚Äč graphs? Choose the correct answer below. So that we can critically analyze a graph to determine whether it is misleading So that we can represent data the way we would like it to look To learn how to draw pictographs To learn how to create frequency distributions
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So that we can critically analyze a graph to determine whether it is misleading
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A‚Äč _______ is a graph of each data value plotted as a point.
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dotplot
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We utilize statistical‚Äč _______ to look for features that reveal some useful or interesting characteristics of the data set.
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graphs
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For data sets having a distribution that is approximately‚Äč bell-shaped, _______ states that about‚Äč 68% of all data values fall within one standard deviation from the mean.
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the Empirical Rule
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The Range Rule of Thumb roughly estimates the standard deviation of a data set as‚Äč _______.
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s= range/4
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Which of the following is NOT a value in the‚Äč 5-number summary? Choose the correct answer below. Median Minimum Mean Q1
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mean
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When a data value is converted to a standardized scale representing the number of standard deviations the data value lies from the‚Äč mean, we call the new value a‚Äč _______.
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z-score
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Which of the following is NOT a property of the standard‚Äč deviation? The units of the standard deviation are the same as the units of the original data. The standard deviation is a measure of variation of all data values from the mean. When comparing variation in samples with very different‚Äč means, it is good practice to compare the two sample standard deviations. The value of the standard deviation is never negative.
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When comparing variation in samples with very different‚Äč means, it is good practice to compare the two sample standard deviations.
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Fill in the blank. In modified‚Äč boxplots, a data value is‚Äč a(n) _______ if it is above Q3plus+‚Äč(1.5)(IQR) or below Q1minus‚ąí‚Äč(1.5)(IQR).
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outlier
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The square of the standard deviation is called the‚Äč _______.
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variance
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Which of the following is NOT a measure of‚Äč center? Choose the correct answer below. census median mode mean
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census
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Which measure of variation is very sensitive to extreme‚Äč values? Choose the correct answer below. Mean Histogram Median Range
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range
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Methods used that summarize or describe characteristics of data are called‚Äč _______ statistics.
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descriptive
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Which of the following is NOT a characteristic of the‚Äč mean? Choose the correct answer below. The mean takes every data value into account. The mean is called the average by statisticians. The mean is relatively reliable. The mean is sensitive to outliers.
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The mean is called the average by statisticians.
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The measure of center that is the value that occurs with the greatest frequency is the‚Äč _______.
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mode
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A value at the center or middle of a data set is‚Äč a(n) _______.
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measure of center
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A data value is considered‚Äč _______ if its‚Äč z-score is less than minus‚ąí2 or greater than 2.
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significantly low or significantly high
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Which of the following is always‚Äč true? Choose the correct answer below. Data skewed to the right have a longer left tail than right tail. The mean and median should be used to identify the shape of the distribution. In a symmetric and‚Äč bell-shaped distribution, the‚Äč mean, median, and mode are the same. For skewed‚Äč data, the mode is farther out in the longer tail than the median.
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In a symmetric and‚Äč bell-shaped distribution, the‚Äč mean, median, and mode are the same.
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Whenever a data value is less than the‚Äč mean, _______.
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the corresponding z-score is negative