Karteikarten
Statistics Module 2
Karten in diesem Stapel (27)
- 1Data consists of:Data consist of INDIVIDUALS and VARIABLES that give us information about those individuals. An individual can be an OBJECT or a PERSON. A variable is an ATTRIBUTE, such as a measurement or a label.
- 2QUANTITATIVE VARIABLESQuantitative variables have numerical values that can be averaged. A quantitative variable is frequently a measurement.
- 3CATEGORICAL VARIABLESCategorical variables have values that are labels. A categorical variable puts individuals into categories.
- 4What is our goal in ANALYZING DATA?In data analysis, our goal is to describe patterns in the data and create a useful summary about a group.
- 5What is our first step in data analysis?From a table of data (hard to see patterns), create a GRAPH of the DISTRIBUTION of the variable
- 6What are the components of DATA?INDIVIDUALS and VARIABLES
- 7What are important descriptors to use in describing distribution of a quantitative variable?1. OVERALL PATTERN:
Shape
Center
Spread
AND
2. Striking DEVIATIONS (outliers) - 8—RIGHT-SKEWED DATA
Lots of data at lower variables and smaller at higher variable values - 9—LEFT-SKEWED DATA
Lots of data at higher variables and fewer at lower variable values
- 10—Bell-Shaped Curve: SYMMETRIC WITH A CENTRAL PEAK: Lots of data in the center with smaller amounts tapering off in each direction.
- 11—UNIFORM: a RECTANGULAR SHAPE, withe the same amount of data for each variable value.
- 12The CENTER of the distributionA single value of the variable to represent the entire group.
- 13What is the SPREAD of the distribution? Two ways to describe spread?VARIABILITY between values.
Described in OVERALL RANGE
and
RANGE OF TYPICAL VALUES - 14An unusually large or small value in a data distributionAn OUTLIER
- 15An alternative way to display the distribution of a quantitative variable, dividing them into equal-sized intervals--particularly useful for large data sets.a HISTOGRAM
- 16What are BINS on a dotplot?Equal-sized intervals (the bars)
- 17What is a percentage of individuals with a given interval of variable values? (Of the sample, what percentage is 100 or over?)Relative frequency
- 18—a HISTOGRAM: dividing large amounts of data into bars of frequency
- 19Frequency is a _____ whereas RELATIVE frequency is a ______Frequency is a NUMBER whereas
relative frequency is a PERCENT - 20What is the MEAN? how is it written in statistics? What are other names for it?Mean + the AVERAGE.
Written x-bar
Other names: balancing point, the FAIR SHARE measure of center. - 21What is the MEDIAN?The MIDDLE of the data when all the values are listed in order. Divides the data into TWO equal sized groups. There's as much data BELOW the median as ABOVE it.
- 22Which is better for summarizing data sets with outliers? What about data sets with a bell shape?With outliers: MEDIAN rather than MEAN, because it doesn't throw off the range as much.
Bell shape: Use MEAN. Any other shape, use median. - 23What is a REPRESENTATIVE VALUE?A central value we assign to describe the whole of a data set, namely MEDIAN and MEAN.
- 24Where is the interquartile range?Between the first and third quartiles. The IQR tells us the middle range (the middle 50%) of the data.
- 25When using the median to measure the center, what should we use as the measure of spread?The InterQuartile Range (IQR) tells us the center, or typical range of values
- 26What's the difference between the variance and standard variance?Variance is calculated by adding the squared deviations and dividing by n-1. Standard variance is the square root of the variance.
- 27Mean and ____ go together Median and _____ go togetherMean and STANDARD DEVIATION.
Median and IQR.
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- Statistics Karteikarten am Statistics Module 2, erstellt von Diana Kleven am 19/06/2017.
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- Diana Kleven
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