Statistical Thinking
This is the term for a number calculated from a simple random sample.
What is a statistic?
These type of data consist of numbers that represent a count or measurement.
What are quantitative (or numerical) data?
This Excel command counts the total number of quantitative data in a column of a spreadsheet.
What is =COUNT(-)?
We use this type of a table to organize data into groups with labels and counts.
What is a frequency distribution?
This is the term for the measure of center with greatest frequency.
What is the mode?
This is the term for the square of the standard deviation.
What is the variance?
Collectively, the minimum, first quartile, median, third quartile, and maximum of a quantitative sample are called by this term.
What is the Five-Number Summary?
This is the term for a number calculated from a census (i.e., an entire population).
What is a parameter?
These type of data consist of names or labels that could be numbers but do not represent counts or measurements.
What are categorical (or qualitative) data?
This Excel command adds the total values of all quantitative data in a column of a spreadsheet.
What is =SUM(-)?
We obtain the relative frequency of a class of data according to this formula.
What is frequency divided by sample size (or total number of data values)?
This is the term for the measure of center that is calculated as the sum of the data values divided by the sample size.
What is the mean?
By the Empirical Rule, approximately this percentage of data values in a bell-shaped distribution fall within two standard deviations of the mean.
What is 95%?
This statistic yields the number of standard deviations that a given data value lies above or below the sample mean.
What is the z-score?
Often, results based on sample data collected from individuals who self-report do not generalize to the population due to this phenomenon.
What is volunteer (or voluntary response) bias?
In this type of study, subjects are observed and certain characteristics are measured without any attempt to modify the individuals.
What is an observational study?
This Excel command produces the value of the first quartile \text{Q1} of all quantitative data in a column of a spreadsheet.
What is =QUARTILE.INC(-, 1)?
Data in a sample that lie sufficiently far from the majority of the other sample values (below \text{Q1} - 1.5(\text{IQR}) or above \text{Q3} + 1.5(\text{IQR}) by definition) are called this.
What are outliers?
We obtain the median of a simple random sample with an even number of data values according to this formula.
What is the sum of the middle two terms divided by two?
By the Range Rule of Thumb, the standard deviation of a sample can be approximated as this quantity.
What is one-quarter of the range (or range divided by 4)?
This statistic is the difference between the third and first quartiles of a quantitative sample; it provides a method to determine outliers among the data.
What is the interquartile range?
If the likelihood of obtaining a result from a simple random sample of data is very small (the most commonly used threshold is 5%), then the result is called by this alliterative term.
What is statistically significant?
Experiments must be conducted so that these three techniques are employed.
What are replication, anonymization, and randomization?
We use this built-in Excel feature to generate descriptive statistics and histograms (and later in the course to conduct statistical inference)?
What is the Data Analysis Toolpak?
If the distribution of a simple random sample is such that the mean, median, and mode are approximately equal and the histogram follows a bell-shaped curve, then the sample is called this.
What is normal (or normally distributed)?
This is the term for a statistic that is typically not affected by extreme values of sample data.
What is resistant?
By the Empirical Rule, approximately this percentage of data values in a bell-shaped distribution fall within three standard deviations of the mean.
What is 99.7%?
This statistic is the number of values less than x divided by the sample size.
What is the percentile value of x?
These types of variables may lead to a spurious correlation between two quantitative variables or prevent the results of an observational study from generalizing to the population.
What are confounding variables?
In this type of sample, the population is divided into (at least) two distinct subgroups that share certain desirable characteristics; then, a simple random sample is drawn from each subgroup.
What is a stratified sample?
We use dollar signs around the column header in Excel to produce this type of cell reference when the value of the cell in question is not changing.
What is an absolute cell reference?
If the distribution of a simple random sample is such that the mean is less than the median, then the sample is called this.
What is left-skewed (or skewed to the left)?
This is the term for a statistic whose sampling distribution is centered at the population parameter.
What is an unbiased estimator?
In a sample with mean \bar x and standard deviation s, values below \bar x - 2s or above \bar x + 2s are said to be this.
What is statistically significant?
In a sample with mean \bar x = 75 and standard deviation s = 5, this is the x-value corresponding to z-score z = 4.2.
What is x = 96?