Learn to Count Data Analysis

Data analysis means looking at a set of numbers and finding meaning in them. If you count how long you slept each night for a week (8, 7, 9, 6, 8, 10, 9), you can analyze: what was the average? 8.1 hours. What was the biggest? 10. What was the smallest? 6. Analysis turns raw numbers into insight.

Three basic analyses: (1) Average (mean): add all numbers, divide by how many. (2) Range: largest minus smallest. (3) Mode: the number that appears most. For sleep (8, 7, 9, 6, 8, 10, 9): mean = 57 ÷ 7 = 8.1. Range = 10 - 6 = 4. Mode = 8 and 9 (tie).

Data analysis is how we turn collections of numbers into decisions. A coach analyzes stats to improve the team. A doctor analyzes blood tests to treat patients. A business analyzes sales to decide what to stock. You analyze your own study time to learn better. Data + analysis = smart decisions.

Mean, median, and mode all describe the middle of a data set, but differently. Mean is the average (add and divide). Median is the middle value when sorted. Mode is the most common. Sometimes they give different answers! For 1, 2, 2, 2, 100: mean = 21, median = 2, mode = 2. The mean is tricked by one big number. Knowing which to use is part of critical thinking.