(M) Data Analysis Flashcards
- well planned research includes a properly planned of this
Data analysis
A. Descriptive statistics
B. Inferential statistics
- Describing the nature and characteristics of the event under investigation
- Measures of Central tendency, Variability or Dispersion, Position or location
- Estimation of parameters
- Make inferences about unknown population parameters based on sample statistics
- Initial step in data analysis of analytic research
- Relationship studies
AABBAB
enumerate MEASURES OF CENTRAL TENDENCY
● Mean
● Mode
● Median
Are measures which describe a typical or representative value in a group of observation
MEASURES OF CENTRAL TENDENCY
● Layman’s concept of “average”
● Value obtained by adding the observations together and dividing this sum by the number of observations in the group
● Center of gravity in a set of observations
● Sensitive to extreme values
● Used especially when other statistical techniques like tests of hypothesis are to be applied to the data
● most common measure of central tendency
Mean
All of this a disadvantage of Mean, except:
A. It is affected by extreme values.
B. It cannot be located graphically.
C. It gives misleading conclusions.
D. It has downward bias.
C (upward bias)
the remaining are the disadvantage
All of this are an advantage of Mean, except:
A. Easy to understand and
simple to calculate
B. It is rigidly defined
C. It is based on all the
values
D. It is based on the position in the series.
E. It is easy to understand even if some of the details of the data are lacking
C (not based)
● Value that occurs most often
● Not affected by extreme values
● There may not be a mode
● There may be several modes
● Used for either numerical or categorical data
MODE
Mode
Not an advantage:
A. readily comprehensible and easily calculated
B. “highlight” of the data set
C. value of mode can also be determined graphically
D. not at all affected by extreme values
E. it is not capable of further
mathematical manipulation.
E
- Mode is affected to a great extent by sampling fluctuations
- not based on all observations.
● Middlemost value in a set of observations whose magnitudes have been ordered or arrayed.
● insensitive to extreme values
● Used when distributions are markedly skewed
● The position of the median value can be calculated using the ff formula
MEDIAN
MEDIAN
Not an advantage:
A. Median can be ascertained
even with the extreme items
B. In case of even no. of values it may not the value from the data
C. Medians can understand even common people.
D. Median can be calculated in all distributions
E. It can be located graphically.
B
Describes how data are distributed
FREQUENCY DISTRIBUTION SHAPES
FREQUENCY DISTRIBUTION SHAPE
Measures of shape
Symmetric or skewed
- Left skewed
- Symmetric
- Right skewed
A. Mean = Median = Mode
B. Mode, Median, Mean
C. Mean, Median, Mode
CAB
Enumerate MEASURES OF VARIABILITY OR DISPERSION
● Range
● Variance
● Standard deviation
● Coefficient of Variation
- Ignores how data are distributed
- Difference between largest and smallest observations
Range
Shows Variation About the Mean
VARIANCE
- usually calculated only when the data are more-or-less “normally distributed”
- For normally distributed data, the arithmetic mean is the recommended measure of central location, and the this is the recommended measure of spread
- In fact, means should never be reported without this
Standard Deviation
paaral po how to calculate for this
● Measure of Relative Variation
● Always a %
● Shows Variation Relative to Mean
● Used to compare two or more groups with different units of Measurements
COEFFICIENT OF VARIATION
MEASURES OF LOCATION OR POSITION for COV
- Divides the distribution into 100 equal parts
- Divides the distribution into 10 equal parts
- Divides the distribution into 4 equal parts
A. Deciles
B. Quartiles
C. Percentiles
CAB
● Measure of variation
● Aka Midspread
○ Spread in the middle 50%
● Difference between 3rd and 1st quartiles
● NOT affected by extreme values
INTERQUARTILE RANGE
