Adding a trend line
Earlier, you saw how a high opening price has a negative correlation with the number of collectibles sold. The resulting scatterplot has a distinct pattern sloping down.
You then visualized the positive correlation between "Seller Rating" and "Close Price" as shown here. Let's now take this further by calculating the slope, intercept, and adding a trend line to better explore the relationship between the two columns.
Spreadsheets have 3 formulas for calculating the y-intercept and slope given two variables.
SLOPE()- will return the slope of a trend line or linear regression representing the linear change in one unit to another.INTERCEPT()- returns the value where the trendline will intersect the y-axis.LINEST()- calculates both the slope & the intercept of two variables using the least-squares method.
이 연습은 강의의 일부입니다
Google Sheets로 배우는 통계 입문
연습 안내
- In cell
D5, calculate theSLOPE()of "Close Price" (B2:B101) and "Seller Rating" (A2:A101). - Similarly, calculate the
INTERCEPT()inE5. - In cell
D9, pass inB2:B101andA2:A101toLINEST(). It will return a values inD9andE9. - Customize the scatter chart series with a trendline by clicking the checkbox.
