GCSE Statistics Key Vocabulary (FULL) Verified Answers

GCSE Statistics Key Vocabulary (FULL) Verified Answers Binomial Distribution ️️Probability of obtaining a specific number of successes out of a given number of trials. Bivariate Data ️️Data sets with two variables. Categorical Data ️️Data that has already been put in to categories or classified in some way. Causality ️️The relationship between an event and a second event. Census ️️Every member of the population is included in the investigation. Choropleth Map ️️Map or diagram where different areas have different shading to represent distribution. Class Width ️️The difference between the upper and lower values of a group. Closed Question ️️A question with a specific answer that can be chosen from a list. Cluster Sampling ️️You include in your investigation one (or more) of the exisiting groups within a population. Comparative Pie Chart ️️Two or more pie charts used to compare sets of data. The total area of each pie chart is in proportion to the total frequency. Continuous Data ️️Data that can take any value (depending on your degree of accuracy). E.g. time, weight, length Control Group ️️A comparison group in an experiment which has been matched as closely as possible with the experimental group (e.g. similar age etc) Convenience Sampling ️️You choose the easiest data to access / easiest people to select without need to number or order a sample frame. Correlation ️️Measure of relationship between two variables. Cumulative Frequency ️️Frequency found by adding each frequency to all the preceding frequencies (a running total). Data ️️Factual information collected for analysis. Discrete Data ️️Data that has specific values - cannot have in-between values. E.g the number of cars in a car park. Double Mean Point ️️The value on a scatter graph where your x coordinate is the mean of all your x values and your y coordinate is the mean of all your y values. Extrapolation ️️Obtaining a prediction/estimate from outside your given data. Frequency ️️How often something occurs. Frequency Density ️️Frequency divided by class width. Independent Events ️️The outcome of the first event does not affect the probability of the second. Index Number (Different to Maths definition) ️️Percentage in relation to a base value. Given by the formula: (Value / base value) x 100 Interpolation ️️Estimating from within the data. Interquartile Range (IQR) ️️Difference between the upper quartile (Q3) and the lower quartile (Q1). i.e. IQR = Q3-Q1 Mean ️️The sum of all the values divided by the number of pieces of data. Median ️️The middle value when arranged in order. Mode ️️The most frequently occuring piece of data. Negative Skew ️️Distribution where the mean is greater than the median but less than the mode. Normal Distribution ️️Distribution represented by a symmetrical curve. 99.7% of the data falls within 3 standard deviations of the mean. Outlier ️️An anomoly. More than 1.5 times the IQR above or below the upper or lower quartiles. Pilot Study ️️Collection of a small amount of data to see if meaningful results can be obtained. Useful to check response rate and the type of data obtained. Population ️️The group you are collecting information about and will apply your results to. Primary Data ️️Data you have collected yourself. Probability ️️The likelihood of an event occuring. Expressed as a fraction or a decimal. Qualitative Data ️️Data that is descriptive - not a number. Quantitative Data ️️Type of data that can be counted or measured.