Microsoft Excel is a commercial spreadsheet application written and distributed by Microsoft for Microsoft Windows and Mac OS X. It features calculation, graphing tools, pivot tables and a macro programming language called Visual Basic for Applications. It has been a very widely applied spreadsheet for these platforms, especially since version 5 in 1993. Excel forms part of Microsoft Office. The current versions are 2010 for Windows and 2011 for Mac.
Linear regression
Introduction to linear regression
Linear regression analyzes the relationship between two variables, X and Y. For each subject (or experimental unit), you know both X and Y and you want to find the best straight line through the data. In some situations, the slope and/or intercept have a scientific meaning. In other cases, you use the linear regression line as a standard curve to find new values of X from Y, or Y from X.
The term "regression", like many statistical terms, is used in statistics quite differently than it is used in other contexts. The method was first used to examine the relationship between the heights of fathers and sons. The two were related, of course, but the slope is less than 1.0. A tall father tended to have sons shorter than himself; a short father tended to have sons taller than himself. The height of sons regressed to the mean. The term "regression" is now used for many sorts of curve fitting.
Prism determines and graphs the best-fit linear regression line, optionally including a 95% confidence interval or 95% prediction interval bands. You may also force the line through a particular point (usually the origin), calculate residuals, calculate a runs test, or compare the slopes and intercepts of two or more regression lines.
In general, the goal of linear regression is to find the line that best predicts Y from X. Linear regression does this by finding the line that minimizes the sum of the squares of the vertical distances of the points from the line.
Note that linear regression does not test whether your data are linear (except via the runs test). It assumes that your data are linear, and finds the slope and intercept that make a straight line best fit your data.
Quadratic Regression is a process by which the equation of a parabola is found that “best fits” a given set of data.Quadratic regression models are often used in economics areas such as utility function, forecasting, cost-befit analysis.
Beer`s law plot data
Titration
answer for question 1
answer for question 2
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