STA 2015
Statistics: Weeks 1-6
Units 1-6 Review Sheet
USLO 1.1 The Importance and Use of Statistics
• Review the case study – Using Stents to Prevent Strokes
USLO 1.2 Data Basics
• Numerical and Categorical Data
o Categorical (Qualitative)
§ Nominal (category) à cereal type, colors
§ Ordinal (order the data) à measurement, ranking
o Numerical (Quantitative)
§ Continuous (interval) à mph, range
§ Discrete (countable) à number of people
• Correlation
o Association ≠ Causation
o Explanatory Variable (independent) à Response Variable (dependent)
o Positive correlation /
o Negative correlation \
USLO 1.3 Sampling Principles and Strategies
• Population: the overall group (all swordfish)
• Sample: a subset of the population
o We want the sample to represent the population
• Anecdotal evidence
o Data collected haphazardly
• Sampling Bias
o Non-response
o Voluntary response
• Observational studies
o Observe the data
o Confounding Variable – another variable that needs to be observed
o Don’t make assumptions!
• Simple Random Sample
, o Random – every member has the same probability of being chosen
• Stratified Sample
o Stratified – population is in groups (ex: area codes) and we randomly grab a few from each strata
• Cluster
o Population is in groups and we randomly grab the entire group
• Convenience
o Getting a sample on what’s convenient – not usually a good idea
• Systematic
o Numbered, grab every 3rd person
USLO 1.4 Experimental Design
• Control Groups and Treatment Groups
o Treatment group receives the drug/treatment
o Control group does not receive any drugs/treatment
• Blinding and Placebos
o Blinding is when researchers keep the patients uninformed
o A fake treatment is called a placebo
• See example on Experimental Design
USLO 2.1 Numerical Data Part 1
• Scatterplots
o Looking for correlation/relationship
§ linear/non-linear
§ positive/negative association
o Review examples
• Dot Plot
o Stacked dot plot
o Review Examples
• Histogram
o “smushed” bar graph
o Review examples
• Skewness
o Histograms are said to be skewed to the side of the long tail
Statistics: Weeks 1-6
Units 1-6 Review Sheet
USLO 1.1 The Importance and Use of Statistics
• Review the case study – Using Stents to Prevent Strokes
USLO 1.2 Data Basics
• Numerical and Categorical Data
o Categorical (Qualitative)
§ Nominal (category) à cereal type, colors
§ Ordinal (order the data) à measurement, ranking
o Numerical (Quantitative)
§ Continuous (interval) à mph, range
§ Discrete (countable) à number of people
• Correlation
o Association ≠ Causation
o Explanatory Variable (independent) à Response Variable (dependent)
o Positive correlation /
o Negative correlation \
USLO 1.3 Sampling Principles and Strategies
• Population: the overall group (all swordfish)
• Sample: a subset of the population
o We want the sample to represent the population
• Anecdotal evidence
o Data collected haphazardly
• Sampling Bias
o Non-response
o Voluntary response
• Observational studies
o Observe the data
o Confounding Variable – another variable that needs to be observed
o Don’t make assumptions!
• Simple Random Sample
, o Random – every member has the same probability of being chosen
• Stratified Sample
o Stratified – population is in groups (ex: area codes) and we randomly grab a few from each strata
• Cluster
o Population is in groups and we randomly grab the entire group
• Convenience
o Getting a sample on what’s convenient – not usually a good idea
• Systematic
o Numbered, grab every 3rd person
USLO 1.4 Experimental Design
• Control Groups and Treatment Groups
o Treatment group receives the drug/treatment
o Control group does not receive any drugs/treatment
• Blinding and Placebos
o Blinding is when researchers keep the patients uninformed
o A fake treatment is called a placebo
• See example on Experimental Design
USLO 2.1 Numerical Data Part 1
• Scatterplots
o Looking for correlation/relationship
§ linear/non-linear
§ positive/negative association
o Review examples
• Dot Plot
o Stacked dot plot
o Review Examples
• Histogram
o “smushed” bar graph
o Review examples
• Skewness
o Histograms are said to be skewed to the side of the long tail
