Normal and Skewed Distribution Flashcards
In a normal distribution, the mean, median, and mode are all located at the ____ and are ____ about the mean.
center, identical
A positively skewed distribution has a tail that extends to the ____ and the ____ is greater than the median.
right, mean
In a normal distribution, approximately ____% of data falls within 2 standard deviations from the mean, while ____% falls within 1 standard deviation.
95, 68
The key characteristic of a normal distribution is its ____ shape, which is also known as a ____ distribution.
bell, Gaussian
In a negatively skewed distribution, the tail extends to the ____ and the ____ is less than the median.
left, mean
To assess if data follows a normal distribution, one can use normality tests such as ____ and ____.
Shapiro-Wilk, Kolmogorov-Smirnov
Understanding distributions is crucial for statistical analysis as it helps to identify ____ in data and choose appropriate ____ tests.
patterns, statistical
In a normal distribution, approximately ____% of data falls within 3 standard deviations from the mean, according to the 68-95-99.7 Rule.
99.7
A histogram is a common tool used to visualize the ____ and ____ of a distribution.
normality, skewness
The left and right sides of a normal distribution curve are ____ images of each other, indicating its ____ nature.
mirror, symmetric
In a distribution where the tail extends to the left, the mean is ____ and the median is ____.
less than,greater than
If one tail of a histogram is longer than the other, the data is ____ and the distribution is ____.
skewed,not normal
In a positively skewed distribution, the relationship between mean and median is that the mean is ____ the median.
greater than
To identify normal or skewed distributions, you can use ____ and ____ as visualization tools.
histograms,box plots
In a box plot, skewness is indicated by a longer ____ or a ____ median line.
whisker,shifted
An example of a normally distributed variable is the ____ of people in a population, while an example of a positively skewed variable is ____ levels in most countries.
heights,income
A test used to check for normality in a dataset is the ____ test.
Shapiro-Wilk
Knowing if data is normally distributed is important because many statistical tests assume ____ for accurate results.
normality
The ‘68-95-99.7 rule’ states that in a normal distribution, 68% of data falls within ____ standard deviation(s) from the mean.
one
Skewness affects statistical analysis by impacting measures of central tendency, particularly the ____, which is pulled towards the skew.
mean
A distribution is skewed when it is not symmetrical and one side of the data stretches further than the _____.
other side
In a positively skewed distribution, the tail of the graph extends to the _____, where larger values are located.
right
In a negatively skewed distribution, the mean is less than the _____ because extreme low values pull the mean downward.
median
A histogram is used to visualize the frequency of data points, while a box plot visualizes the _____ and skewness of data.
spread
In a positively skewed distribution, the mean is greater than the _____ because extreme high values pull the mean upward.
median
A normal distribution appears as a bell-shaped curve, while a positively skewed distribution has a long tail on the _____.
right
The mean, median, and mode are not the same in a skewed distribution, unlike in a _____ distribution.
normal
The 68-95-99.7 rule states that 68 percent of data falls within one standard deviation from the mean, while 95 percent falls within _____ standard deviations.
two
In healthcare, understanding distributions is essential for monitoring patient data like _____ and _____ pressure.
blood, blood
A negatively skewed distribution has a long tail on the left, where smaller values are located, and the mean is _____ than the median.
less
In a positively skewed distribution, the mean is pulled toward ____ values and is greater than the ____.
higher, median
In a negatively skewed distribution, the mean is pulled toward ____ values and is less than the ____.
lower, median
A normal distribution is identified by a histogram that forms a ____ curve and is ____ shaped.
bell, symmetric
Skewness can be identified in a box plot by a longer ____ on one side or a median line that is not ____.
whisker, centered
An example of a variable that follows a normal distribution is the ____ of adults in a population, which is typically ____ around a central value.
heights, symmetric
An example of a positively skewed variable is ____ levels, where a few individuals earn significantly more than the ____.
income, majority
An example of a negatively skewed variable is the ____ of retirement, where most retire around a standard age but some retire much ____.
age, earlier
Understanding the type of distribution in data is important to choose the correct ____ analysis methods and interpret results ____.
statistical, accurately
Skewness distorts the mean, making it less reliable as a measure of ____ tendency and affecting the overall ____ of the data.
central, interpretation
A real-world use of normal distribution in healthcare is monitoring patients’ ____ pressure, which often follows a ____ pattern.
blood, normal
Standard deviations are important in a normal distribution because they help determine how much of the data falls ____ the mean, indicating data ____.
near, consistency
To identify a normal distribution from raw data, look for symmetry around a central value, where the mean, median, and mode are ____ or very ____.
close, identical
In a normal distribution, there are few extreme values or ____, and the range of data is similar on both sides of the ____.
outliers, mean
In a positively skewed distribution, the mean is greater than the median and the mode, which can be represented as Mean > _____ > _____.
Median, Mode
In a negatively skewed distribution, the majority of data points are clustered at the higher end, leading to the relationship Mean < _____ < _____.
Median, Mode
A normal distribution is characterized by symmetry around the mean, where the mean, median, and mode are approximately equal, represented as Mean ≈ _____ ≈ _____.
Median, Mode
In a positively skewed distribution, extreme high values can significantly influence the mean, while in a negatively skewed distribution, extreme low values affect the mean. This can be summarized as the presence of extreme _____ or _____.
high values, low values
When analyzing data, it is important to check for outliers, which are extreme values that can impact the _____ and _____ of the dataset.
mean, median
In a normal distribution, the data points are evenly spread around the mean, while in a skewed distribution, the range is uneven, with one side having more extreme values. This can be summarized as equal range on both sides of the mean versus _____ range on one side.
uneven
An example of a positively skewed distribution is annual income, where most incomes cluster around lower values, but a few extreme values can skew the mean upward. This is represented by data points like 20,000, 25,000, and _____.
1000000
In a negatively skewed distribution, the majority of data points cluster near the upper end, such as in retirement ages where most individuals retire around 60, but a few retire much earlier, leading to a mean that is _____ than the median.
lower
To identify a skewed distribution from raw data, one should observe the cluster patterns and check how the mean, median, and mode relate to each other, particularly looking for _____ or _____ values.
extreme high, extreme low
In a positively skewed distribution, the data points are often clustered at the lower end, with a few very high values, such as in the example of 10, 12, 14, 15, and _____.
100
