This definitions covers Key Terms within Graph, Chart and Data Skills for GCSE Geography. Revise Graph, Chart and Data Skills in Geographical Skills for GCSE Geography with 15 exam-style questions and 20 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 8 of 13 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Topic position
Section 8 of 13
Practice
15 questions
Recall
20 flashcards
📖 Key Terms
Trend — The overall direction of change in a dataset over time or across locations. Expressed qualitatively (increasing, decreasing, fluctuating, stable) and supported by specific data values. Example: "Global average temperature shows an upward trend from −0.2°C anomaly in 1880 to +1.2°C anomaly in 2020."
Anomaly — A single data point, period, or place that does not fit the general trend. Anomalies should be identified, described with a precise value, and explained with reference to geographical factors. A well-explained anomaly demonstrates interpretation skills and is worth significant marks.
Correlation — A statistical relationship between two variables where a change in one is associated with a change in the other. Positive correlation: both increase together. Negative correlation: one increases as the other decreases. Correlation does NOT prove causation.
Annual temperature range — The difference between the hottest and coldest monthly average temperatures in a climate graph (highest – lowest, in °C). A large range (over 20°C) typically indicates a continental location far from the sea. A small range (under 10°C) indicates a maritime or tropical location.
Birth rate — The number of live births per 1,000 people per year. A birth rate above 30 per 1,000 is considered high (typically LICs); below 15 per 1,000 is low (typical of HICs and ageing populations). Birth rate is shown on population pyramids by the width of the youngest cohorts.
Death rate — The number of deaths per 1,000 people per year. High death rates reflect limited healthcare access and high rates of disease; low death rates reflect effective medical systems and good living standards. On a population pyramid, rapid tapering above young cohorts indicates a high death rate.
Life expectancy — The average number of years a person born in a country can expect to live. Reflects healthcare quality, nutrition, and living conditions. On a population pyramid, shown by how far the bars extend upward — wide bars above age 70 indicate high life expectancy.
Dependency ratio — The ratio of "dependants" (those aged under 15 or over 65, who are not typically in paid work) to the working-age population (15–64). A high youth dependency ratio (as in LIC population pyramids) places financial pressure on a small working-age base to support schools, healthcare, and food supply for large young populations.
Median — The middle value in an ordered dataset. More representative than the mean when data contains outliers (extreme values). Used for income, house prices, and other economic data where a small number of very high values would distort the mean upward.
Interquartile range (IQR) — The range of the middle 50% of data values (Q3 − Q1). Less distorted by outliers than the full range, making it a more reliable measure of spread for datasets with extreme values.
Positive correlation — A relationship where as one variable increases, the other also tends to increase. On a scatter graph, points cluster around a line of best fit rising from bottom-left to top-right. Example: GDP per capita and life expectancy.
Negative correlation — A relationship where as one variable increases, the other tends to decrease. On a scatter graph, points cluster around a line of best fit falling from top-left to bottom-right. Example: GDP per capita and birth rate.