Statistical Theorems
General Statistical Knowledge
STATISTICAL DISTRIBUTIONS
Graphs and Plots
Data Types
100
The average of the squared distances from the mean when calculated is called
What is the variance
100
T-distribution BINOMIAL POISSON EXPONENTIAL
In this course, we primarily concentrated on the NORMAL distribution. WHAT ARE 2 OTHER TYPE OF DISTRIBUTIONS MENTIONED?
100
True or False. Explain your answer. The data for a NORMAL distribution must be discrete
What is False. Must be continuous random
100
A plot that is best used to show percentages in each category would be a
What is a pie chart
100
Data can be classified into 2 general broad categories. Both start with the same letter of the alphabet.
What are qualitative and quantitative
200
The only items we know about a sample distribution is the sample size is 50, MEAN is = to 28, STANDARD DEVIATION IS 3. WHAT IS THE MINIMUM # OF OBSERVATIONS THAT FALL IN THE INTERVAL (22, 34)?
What is approximately 38 CHEBYSHEV states that 75% of data falls within 2 standard deviations of mean, while 88.9% falls within 3 standard deviations of mean. (22, 34) is 2 standard deviations form mean so .75 x 50 = 37.5 rounded up to 38 since minimum.
200
30
When statisticians or those using statistics refer to "large " sample sizes, the number that is typically assumed to be a large sample is typically > or = to what sample size
200
For a normal distribution curve, the area under its curve is = to and its horizontal tails are called
What is 1 and asymptotes
200
A plot that would show cumulative frequencies or values
What is an ogive
200
Quantitative data can be classified into 2 types
What are continuous and discrete
300
We know that from much data collected, the distribution of new born baby weights is bell shaped with a MEAN of 3000 grams and a STANDARD DEVIATION of 500 grams. We would like to know the % of new born babies that are born between 2000 and 4000 grams. THE STATISTICAL RULE OR THEOREM COULD BE USED IN THIS SCENARIO TO ESTIMATE THE % AND WHY CAN IT BE USED?
What is EMPIRICAL. The rule can be applied to a distribution that is considered bell shaped
300
The measure of central tendency that is most affected by outliers?
What is the the MEAN
300
The t-distribution is similar to the standard normal distribution curve but not as accurate. Compare on the same graph a standard normal distribution curve and t-distribution curves with degrees of freedom of 2 and 20
What is 20 degrees of freedom approaching closely the standard normal
300
Among the following plots/graphs, which 2 would best graphically display outliers: Box Plot, Pie Chart, Scatter Plot, Pictogram, Bar Chart
What is a Box Plot and Scatter Plot
300
The weight of newborn children would be considered this specific type of data
What is quantitative, continuous
400
The percentage of the data in a normal distribution that is between the mean and 2 standard deviations above the mean?
What is 47.5%
400
The term that describes how many standard deviations from the mean a particular value lies from the mean?
What is a Z-score or standard score
400
You have decided to use a t-distribution curve becasue the sample size is small, which is = to 20. How many degrees of freedom would be used in this instance?
What is 19
400
https://lh3.google.com/u/0/d/0ByurVtuTJmP-SHZ2aHZtR1BEejlsU0JBVGc5SnNoVU0tMnJF=w2560-h1219-iv1 From the plot, the number of students who received grades between 50 and 70% were
What is 20
400
A type of data variable that has implied ordering and distance between successive numbers and has an absolute zero point would be called (Age and weight are applications of this type of data variable)
What is a ratio variable
500
SAMPLE SIZE IS < 30 or the STANDARD DEVIATION IS UNKNOWN A student - t distribution can be used when the distribution approximates a normal distribution and 1 of 2 other conditions are met. THE 2 CONDITIONS IN ORDER TO USE THE t - distribution?
What is sample size < 30, or unknown standard deviation
500
The normal distribution and standard normal distribution are very similar curves. The 2 properties and their values that make the normal distribution a standard normal distribution
What is MEAN = 0, STANDARD DEVIATION = 1
500
Which is true about a Normal Distribution a. The mean, mode, and median are never equal b. The mean, mode, and mean are equal c. The mean is 0 and the mode and median are equal to 1 d. The median is 1 and the mode and mean are = to 0
What is statement b.
500
If the mean is > median > mode, we would tend to say the distribution plot is skewed in which way right or positive, left or negative, symmetric, uniform, logarithm
What is right or positive
500
The ONLY measure of tendency that can be used with categorical or nominal data is
What is the mode
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