https://community.esri.com/t5/geoprocessing-questions/dimension-reduction-first-time-user/m-p/1416778#M27260 <P>Good evening,</P><P>This is my first time using the Dimension Reduction tool and unfortunately, there really aren't any Esri videos that talk about this tool. So I have census tract level data containing 30 different variables (covering race, age/sex, income, housing, health, total population, education) and I was trying to reduce these variables by splitting them into 7 components using the Dimension reduction tool. I ran the tool with a number of permuations of 99 and the tool ran fine, however I'm finding it difficult to delineate which variabales belong to which component. With that, these are my questions:</P><P>1. Using the eigenvalues table and chart (I have attached them), how can I tell which variables make up each component? The goal is to use these 7 components for a flood vulnerability analysis (I want to use an ANOVA to see if there any differences across these components within and outside the flood zones).</P><P>2. My understaning of the Broken stick value from this documentation (<A href="https://pro.arcgis.com/en/pro-app/latest/tool-reference/spatial-statistics/how-dimension-reduction-w" target="_blank">https://pro.arcgis.com/en/pro-app/latest/tool-reference/spatial-statistics/how-dimension-reduction-w</A>...) is that, it tells me the optimal number of components. Based on my scree plot (also attached), the intersection was at '8' with a 70% total variance explained but in the output message window (also attached), a value of 3 was given. However when I ran the tool without inputting any number of components, that value changed to '28' with a 100% variance explained. Can some light be shed on this please as it has me very confused.</P><P>3. Lastly, for the Bartlett's test of Sphericity, the number of components is 28 (see attached output message window). Does this mean that only 28 variables are relevant?</P><P>Please any sort of assistance on this will be very useful and I will be extremely grateful.</P><P>Also, if you feel there is a better way to go about this in ArcPro, I'm more than open to working with your suggestions.</P><P>Thank you.</P> Mon, 29 Apr 2024 23:02:24 GMT NakkyEkeanyanwu 2024-04-29T23:02:24Z https://community.esri.com/t5/geoprocessing-questions/dimension-reduction-first-time-user/m-p/1416778#M27260 <P>Good evening,</P><P>This is my first time using the Dimension Reduction tool and unfortunately, there really aren't any Esri videos that talk about this tool. So I have census tract level data containing 30 different variables (covering race, age/sex, income, housing, health, total population, education) and I was trying to reduce these variables by splitting them into 7 components using the Dimension reduction tool. I ran the tool with a number of permuations of 99 and the tool ran fine, however I'm finding it difficult to delineate which variabales belong to which component. With that, these are my questions:</P><P>1. Using the eigenvalues table and chart (I have attached them), how can I tell which variables make up each component? The goal is to use these 7 components for a flood vulnerability analysis (I want to use an ANOVA to see if there any differences across these components within and outside the flood zones).</P><P>2. My understaning of the Broken stick value from this documentation (<A href="https://pro.arcgis.com/en/pro-app/latest/tool-reference/spatial-statistics/how-dimension-reduction-w" target="_blank">https://pro.arcgis.com/en/pro-app/latest/tool-reference/spatial-statistics/how-dimension-reduction-w</A>...) is that, it tells me the optimal number of components. Based on my scree plot (also attached), the intersection was at '8' with a 70% total variance explained but in the output message window (also attached), a value of 3 was given. However when I ran the tool without inputting any number of components, that value changed to '28' with a 100% variance explained. Can some light be shed on this please as it has me very confused.</P><P>3. Lastly, for the Bartlett's test of Sphericity, the number of components is 28 (see attached output message window). Does this mean that only 28 variables are relevant?</P><P>Please any sort of assistance on this will be very useful and I will be extremely grateful.</P><P>Also, if you feel there is a better way to go about this in ArcPro, I'm more than open to working with your suggestions.</P><P>Thank you.</P> Mon, 29 Apr 2024 23:02:24 GMT https://community.esri.com/t5/geoprocessing-questions/dimension-reduction-first-time-user/m-p/1416778#M27260 NakkyEkeanyanwu 2024-04-29T23:02:24Z