Multi-Sigma Help
Frequently Asked Questions
Q&A
The task screen doesn’t appear after creating a neural network analysis task, or input and output file saving doesn’t complete in Bayesian analysis.
In Multi-Sigma, text data analysis is not supported. If your data contains text data other than in the header section, it may result in a system error. Please make sure your data doesn’t contain any text data when uploading it.
Can multiple people in our department use the trial version?
For the trial version, we please request that only one representative from your department registers. Each account can only submit one job at a time, so please coordinate the usage among multiple users to avoid conflicts.
In factor analysis, if the contribution of a specific parameter is too high, will it overshadow other parameters?
Since the contribution values sum up to 100%, it is possible for a highly contributing parameter to overshadow others. To address this, you can narrow the range of values for highly contributing parameters during analysis, which may make it easier to observe the effects of other parameters.
When dealing with sparse data, which is common in our case, what should we do to improve AI learning?
Multi-Sigma offers a feature to generate experimental conditions randomly. You can conduct experiments using these conditions and combine them with your past experimental data as input. This way, you can effectively use your existing data for AI learning.
Is there a visualization feature for the results?
While Multi-Sigma has a graphing feature for AI prediction results, it displays only the last few dozen data points. To view the entire dataset, it’s recommended to download the result file and visualize it using tools like Excel.
How can I visualize the results of multi-objective optimization?
You can create a two-dimensional graph with the most important objective variable plotted on the x-axis and the next most important one on the y-axis. Alternatively, you can download the multi-objective optimization result file, normalize each objective variable by dividing them by their maximum values, and then visualize the normalized data.
What’s the recommended data split ratio between training and validation data?
A good starting point is a 9:1 ratio for training and validation data. You can use Excel’s RAND() function for randomization when splitting the data.
My prediction accuracy is not very good.
If the auto-tuning feature for AI learning doesn’t improve prediction accuracy, consider adjusting how you create the training data, increasing the amount of training data, or understanding that some problems may inherently have low prediction accuracy regardless of the method used.
I want to find the optimal ratio between A and B, with A + B equal to 100%. Is this possible?
You can achieve this by including either A or B in the training data. Alternatively, include both A and B in the training data and use constraints during optimization, setting the coefficients of A and B to 1 while ensuring they sum up to 1 (or 100%).
I have around 50 explanatory variables and about 15 target variables, with data of about 50,000 rows. Is it possible to perform the analysis? If it seems challenging, I’m willing to reduce the data by removing similar data or zones with no demand. Could you provide guidance on the approximate limit?
The maximum data size you can upload for one analysis (project) is 3MB. It’s possible that your data may exceed this size. If you encounter this issue, as you mentioned, you can consider reducing the data by removing some portions. We are exploring options for handling larger datasets in future developments.
Is it possible to filter the Pareto solutions from the solution set?
In Multi-Sigma, you can obtain sets of Pareto solutions for multiple objective variables. You can download these results and use software like Excel to extract the solutions that offer the best balance of objective variables.
Can qualitative data be handled?
Yes, it’s possible. You can convert qualitative data into numerical values. For example, you can assign numerical values like “0” for “Male” and “1” for “Female” to handle gender data.
Example 1:
Age Height Weight Gender
25 172.2 62.7 Male
32 159.3 57.2 Female
48 168.5 65.1 Male
↓ Convert Gender to Numerical Values
Age Height Weight Gender
25 172.2 62.7 0
32 159.3 57.2 1
48 168.5 65.1 0
Example 2:
Age Height Weight Blood Type
25 172.2 62.7 A
32 159.3 57.2 B
48 168.5 65.1 O
↓ Convert Blood Type to Numerical Values
Age Height Weight A B O
25 172.2 62.7 1 0 0
32 159.3 57.2 0 1 0
48 168.5 65.1 0 0 1
When data volume increases, can I save only the AI model and later import it into Multi-Sigma?
Currently, this functionality is not available. While you can download the AI model you’ve created, it’s intended to be used outside of Multi-Sigma, such as in Python. We are considering the possibility of adding project and AI model backup features in the future.
I have multiple material candidates, and I ultimately want to use around two of them. Should I include all the materials in experiments, even if some seem unlikely to be used?
It’s advisable to include all material candidates in experiments. You can use factor analysis to determine the contributions of each material. During optimization, you can set the maximum and minimum values of materials you don’t want to use to be the same, effectively optimizing only the materials you want to use.
Is it possible to create VS plots to compare the prediction accuracy of multiple models created for ensemble purposes?
Currently, there’s no built-in feature for this. To compare prediction accuracy, download the prediction results from each model and compare them manually to the ground truth data using tools like Excel. We may consider adding this feature in future developments.
Is there a feature in Multi-Sigma that instructs on what kind of experimental data to take when there is bias in the distribution of experimental data?
You can use the “Data Profiling” feature to visualize the distribution of your data. This can help you identify trends in missing data and decide what kind of experimental data to collect next to address any biases. Additionally, using Bayesian optimization can prioritize gathering data from sparse regions to improve the overall dataset.
How are missing values in the data handled?
Data with missing values will result in an error. To handle missing values, you should either impute them using an appropriate method or remove rows with missing data before uploading the dataset.
If there are continuous data with singular changes in between, can they be analyzed in the same way?
You can analyze data with singular changes, but it’s important to consider the presence of these singularities. Singularities or abrupt changes in the data can significantly impact the analysis and modeling process. It’s crucial to preprocess the data and choose appropriate modeling techniques to handle such cases effectively.
Can variables with significantly different scales be analyzed?
In general, having variables with different scales can negatively impact predictive accuracy in neural networks. Therefore, Multi-Sigma performs data preprocessing to standardize or normalize the numerical scales before analysis.
Are there any restrictions on the data type of numerical values used?
There are no restrictions. You can use either integers or real numbers (decimal values). When performing optimization, you can choose whether each explanatory variable should be treated as an integer or real number.
What level of prediction error can be considered “high prediction accuracy”?
In the field of physics, an error of around 10% is often considered high accuracy. In the field of biology, a prediction error of around 20% is considered reasonable.
The analysis has been running for a whole day and hasn’t finished. Why is that?
It’s possible that the page hasn’t been refreshed. Please try refreshing the page by pressing the CTRL key and F5 key simultaneously.
How is the contribution score calculated?
Multi-Sigma uses the Partial Derivative (PaD) method described in Gevrey et al. (2003) to calculate the contribution scores.
Are there any marketing use cases for Multi-Sigma?
Multi-Sigma has been used in the past for optimizing features and specifications of new technologies based on consumer purchase probability from survey data. Currently, it is being used for demand and sales forecasting for aluminum can beverages as part of a NEDO project. However, these cases may not have publicly available materials.
I accidentally clicked on “Auto-tuning Training” in AI learning, but I can’t click on “Force Terminate”. What should I do?
While the job status is “CREATED,” the analysis library is being loaded, and you’ll need to wait. Once the training starts and the job status changes to “RUNNING,” you should be able to click on “Force Terminate” to halt the training.