Descriptive Stats/Research (wk 4) Flashcards
What three ways can you describe continuous data?
- Distribution (unimodal, bimodal, multimodal, right or left skewed)
- Measure its center (mean, median, mode)
- Measure its spread (narrow or broad distribution)
What type of graph do you draw to check the distribution of continuous variables?
Histogram
T/F Normal distribution represents an important statistical concept because many data from biological, psychological and social phenomena follow this shape
True
What is the most common value for central tendency of continuous data/?
Mean
Which measure of center value for continuous data is the best for data with an outlier or data that is distributed skewed?
Median
Which measure of center value for continuous data represents the highest bar in a histogram, but is often rarely reported?
Mode
What is the relationship of Mean, Median, and Mode for data distributed symmetrical?
mean = median = mode
What is the relationship of Mean, Median, and Mode for data distributed skewed to the right?
mode < median < mean
What is the relationship of Mean, Median, and Mode for data distributed skewed to the left?
mean < median < mode
What is the most common value for spread of the data around the mean?
SD
What is the most common value for spread of the data around the median, though can be misleading in data with an outlier?
Range
What measurement of Q3-Q1 measure better than range does for data with an outlier?
Interquartile Range (IQR)
Ex: Range 8.8-15 with mean of 12.1 (normally distributed with SD = 1)
What is the approximate proportion of those whose calcium values are below 10.1?
2.5%
For data normally distributed, the mean (SD) are reported. For data that is skewed, the ___ (___) are reported.
Median (IQR)
For categorical data you find the ____, the numbers in each category and the ____, the percentage.
Frequency – numbers in each category
Proportion - precentage
What type of research has variables that you can’t control, but whose results can provide the basis for further research?
Descriptive research
WHy use descriptive research?
i. To define subject characteristics
ii. To measure data trends
iii. To validate existing conditions
Disadvantages of descriptive research?
- Response and non-response bias
2. Limited scope of WHAT with no info on WHY
T/F Descriptive research is used to make predictions
False, correlational research is
Type of descriptive study with the purpose that you present as complete a picture as possible about the characteristics and exposures of individual case
Case report study
T/F Case report study provides sufficient control to allow for generalizations or conclusions about causality.
False, it does not provide, can only act as a catalyst for further study
Type of descriptive study with the purpose to provide overall picture of group’s characteristics often using survey to collect the information.
Descriptive survey
Type of descriptive study with the purpose to describe the of developmental change and the sequencing of behaviors in people over time
Development research
Type of descriptive study with the purpose to describe typical or standard values for characteristics of a given population (specific age, gender, occupation, culture or disability)
Normative Study
