{
 "source": "https://peabody.kids/flashcards/math-statistics-terms",
 "id": "math-statistics-terms",
 "title": "Statistics Terms",
 "category": "math",
 "subject": "Math",
 "levels": [
  "6-8",
  "9-12",
  "college"
 ],
 "description": "Descriptive and inferential statistics vocabulary, from mean and median to confidence intervals.",
 "tags": [
  "statistics",
  "data"
 ],
 "frontLabel": "Term",
 "backLabel": "Meaning",
 "cards": [
  [
   "Data",
   "Facts or measurements that have been collected"
  ],
  [
   "Population",
   "The whole group you want to learn about"
  ],
  [
   "Sample",
   "A smaller group taken from the population"
  ],
  [
   "Random sample",
   "A sample where every member of the population has an equal chance of being chosen"
  ],
  [
   "Bias",
   "A systematic error that tilts results in one direction"
  ],
  [
   "Survey",
   "A way of collecting data by asking people questions"
  ],
  [
   "Census",
   "A survey of every member of the population"
  ],
  [
   "Variable",
   "A characteristic that can take different values"
  ],
  [
   "Categorical data",
   "Data sorted into groups or names",
   "Eye color"
  ],
  [
   "Numerical (quantitative) data",
   "Data that are numbers you can measure or count"
  ],
  [
   "Discrete data",
   "Data that can only take separate values, like counts"
  ],
  [
   "Continuous data",
   "Data that can take any value in a range, like height"
  ],
  [
   "Mean",
   "Sum of all values divided by how many values"
  ],
  [
   "Median",
   "Middle value of ordered data"
  ],
  [
   "Mode",
   "Most frequently occurring value"
  ],
  [
   "Range",
   "Maximum minus minimum"
  ],
  [
   "Outlier",
   "A value far away from the rest of the data"
  ],
  [
   "Quartile",
   "One of three values that split ordered data into four equal parts"
  ],
  [
   "Q1 (first quartile)",
   "The median of the lower half of the data"
  ],
  [
   "Q3 (third quartile)",
   "The median of the upper half of the data"
  ],
  [
   "Interquartile range (IQR)",
   "Q3 − Q1"
  ],
  [
   "Five-number summary",
   "Minimum, Q1, median, Q3, maximum"
  ],
  [
   "Outlier rule (1.5 × IQR)",
   "Values below Q1 − 1.5·IQR or above Q3 + 1.5·IQR are flagged as outliers"
  ],
  [
   "Percentile",
   "The value below which a given percent of data fall"
  ],
  [
   "Variance",
   "The average squared distance from the mean"
  ],
  [
   "Standard deviation",
   "The square root of variance; typical distance from the mean"
  ],
  [
   "Z-score",
   "How many standard deviations a value is from the mean: (x − mean)/s"
  ],
  [
   "Frequency",
   "How many times a value occurs"
  ],
  [
   "Relative frequency",
   "Frequency divided by the total count"
  ],
  [
   "Cumulative frequency",
   "A running total of frequencies"
  ],
  [
   "Histogram",
   "A bar graph for numerical data grouped into intervals"
  ],
  [
   "Box plot (box-and-whisker)",
   "A graph of the five-number summary"
  ],
  [
   "Dot plot",
   "A graph with a dot above a number line for each data value"
  ],
  [
   "Stem-and-leaf plot",
   "A table that splits each value into a stem and a leaf"
  ],
  [
   "Scatter plot",
   "A graph of ordered pairs showing how two variables relate"
  ],
  [
   "Bar graph",
   "A graph using separate bars to compare categories"
  ],
  [
   "Pie chart",
   "A circle graph that shows parts of a whole"
  ],
  [
   "Line graph",
   "A graph that connects points to show change over time"
  ],
  [
   "Symmetric distribution",
   "The left and right sides mirror each other"
  ],
  [
   "Skewed right",
   "A longer tail on the right; mean is usually greater than median"
  ],
  [
   "Skewed left",
   "A longer tail on the left; mean is usually less than median"
  ],
  [
   "Normal distribution",
   "A symmetric bell-shaped distribution"
  ],
  [
   "Empirical rule",
   "About 68%, 95% and 99.7% of normal data fall within 1, 2 and 3 standard deviations of the mean"
  ],
  [
   "Correlation",
   "A measure of the strength and direction of a linear relationship"
  ],
  [
   "Correlation coefficient (r)",
   "A number from −1 to 1 measuring linear correlation"
  ],
  [
   "Positive correlation",
   "As one variable increases, so does the other"
  ],
  [
   "Negative correlation",
   "As one variable increases, the other decreases"
  ],
  [
   "Correlation vs. causation",
   "Two things moving together does not prove one causes the other"
  ],
  [
   "Line of best fit",
   "A line drawn to match the trend in a scatter plot"
  ],
  [
   "Regression",
   "A method for fitting a model to describe how one variable depends on another"
  ],
  [
   "Residual",
   "Actual value minus predicted value"
  ],
  [
   "Extrapolation",
   "Predicting beyond the range of the data"
  ],
  [
   "Interpolation",
   "Predicting between known data points"
  ],
  [
   "Hypothesis test",
   "A procedure for deciding whether data support a claim"
  ],
  [
   "Null hypothesis",
   "The default claim that nothing special is going on"
  ],
  [
   "P-value",
   "The probability of results at least as extreme as observed if the null hypothesis is true"
  ],
  [
   "Confidence interval",
   "A range of values likely to contain the true population value"
  ],
  [
   "Margin of error",
   "The amount added and subtracted from an estimate to form an interval"
  ],
  [
   "Sampling distribution",
   "The distribution of a statistic over many samples"
  ],
  [
   "Central limit theorem",
   "Sample means tend toward a normal shape as sample size grows"
  ],
  [
   "Control group",
   "The group in an experiment that does not get the treatment"
  ],
  [
   "Random assignment",
   "Using chance to place subjects in experiment groups"
  ],
  [
   "Observational study",
   "A study that observes without assigning treatments"
  ],
  [
   "Experiment",
   "A study where researchers assign treatments"
  ]
 ]
}