Ten Berge Exponent Calculator

INSTRUCTIONS:

1. Download the template table from the link below as a .csv file, input the data for the desired chemical(s), save locally, and then upload the file at the top of the 'File Input' page. A table will be displayed. Please thoroughly read through the table to ensure you have entered the data correctly.

Link to Template

Please refer to 'Worked Example' link for correct variable input format.(e.g.'hr' for unit in hours)

Worked Example

2. The 'Data Visualization' tab will produce scatter plots of the log(Concentration) vs. log(time) for the chemical(s)selected at the top of the page.Each chemical will have its own set of graphs (if data for different species is available.

3. The 'Regression Visualization' tab will produce scatter plots only for chemicals which pass filtering (have at least 3 unique time observations with one species). The scatter plot will include the regression line along with a visualization of the uncertainty surrounding the regression estimation.

4. The 'Regression Model Results' tab will include a table and a graphical display of the estimates with Bayesian Credible intervals for the exponent, n, for each chemical-species combination.

5. The 'Mixed Effects Model Results' tab will include results of a mixed effects model which includes a random effect to account for correlation between outcomes of observations coming from the same study (the Reference). This will only make sense to interpret in specific scenarios which are outlined in the 'Methodology' tab.

FOR FIRST TIME USER:

Refer to the 'Worked Example' link above to see a walk-through of the app usage for a real example dataset.

FOR MORE INFORMATION:

Refer to the 'Methodology' tab for more information on methodology used and references.

Note that in this tab, only chemical(s) that have at least 3 observations from different time points for one species can be used to fit the regression model. If no visualization is displayed in this tab, please carefully check the data to make sure minimal requirement is met.

Note that in this tab, only chemical(s) that have at least 3 observations from different time points for one species can be used to fit the regression model. If no visualization is displayed in this tab, please carefully check the data to make sure minimal requirement is met.

Note that in this tab, only chemical(s) that fits the following requirements can be used to fit the mixed effects model: (1)at least 3 observations from different time point, (2)among which at least two observations are from the same study/reference, (3)the above-mentioned observations are for the same species. If no visualization is displayed in this tab, please carefully check the data to make sure minimal requirement is met.

In this project, both linear regression model and mixed effects model methods derived basic form from the Standard Operating Procedures but differs in taking or without taking study-to-study (References) variability into account. For the MEM method, component was added to adjust for the variation between each study

Please refer to the following reports for details:

FULL REPORTS:

1. Regression Model - Matthew Snyder & Takumi Kijima

2. Mixed Effects Model - Lizzy Compton & Jacob Smith