Mystery solved! The secret of Excel curved line interpolation

Excel Interpolation: A Black Box No Longer

Have you ever wondered what formula Excel uses to make its “curved line” scatter plots? I have!

Admittedly, this sounds like an odd thing to wonder about. But it’s actually a super-practical question: what if you want to approximate an intermediate point along the curve you have just plotted? For some reason, Excel hides this formula from you, and according to my source post, Microsoft has left this formula a black-box and given users no access to it. WTF, mate. Continue reading Mystery solved! The secret of Excel curved line interpolation

Coming Soon: New iPhone App

5 months ago, we released our initial mobile apps for iPhone and Android. We’ve had great success with the apps and it’s long past time we updated them! I joined the team a month ago and started working on a new app for the iPhone – which is now waiting on approval from Apple and should be available some time next week.

Continue reading Coming Soon: New iPhone App

Rent your furniture instead of buying?

Cort
Hate dealing with furniture?

While the Splitwise furniture calculator can help you deal with buying shared furniture (and who gets to keep it when you move out), the hassle of shopping for and hauling furniture is definitely one of the worst parts of moving. An article in SF Gate last week mentions an interesting new service called CORT which will help you rent all the furniture in your apartment all at once. Continue reading Rent your furniture instead of buying?

Splitwise’s Updated Quick-Add Feature

Now live on Splitwise (and within your Splitwise iPhone or Android app) is a big update to our favorite little Splitwise feature: Quick-Add. This feature makes it really easy to add in new shared expenses, payments, loans, and IOUs!

Now with English verbs!

Continue reading Splitwise’s Updated Quick-Add Feature

Happy MLK Day From Splitwise

Today is a celebration of America’s greatest champion for fairness, who would have turned 83 this year. Even if you are working today (as we are here at Splitwise) and not taking the day off, there’s always time to read and reflect on what the day stands for:

  • MLK’s Wikipedia article. While Martin Luther King is best remembered for his achievements in Civil Rights, he was also an advocate for economic justice and fairness for the poor.
  • Google Doodle for MLK day. This link also has a flashback to Google’s earlier tributes.
  • CNN’s coverage including some Obama quotes and added context.

Juries: The Original Fairness Calculator

Jury
A survey of your peers.

I had the fascinating experience of attending my first jury summons yesterday in the Commonwealth of Massachusetts. I wasn’t sure whether to be disappointed or relieved when they dismissed me from the courthouse after 7 hours of waiting for my voir dire.

A randomly selected jury pool jury is in some ways the original, single-use fairness calculator. When confronted with a dispute, one presents the case to a representative sample of your peers. They vote for the result they think matches their common sense notions of what is relevant and who is right. If Splitwise didn’t do surveys to test our fairness calculators, it would be a bit like the government having a trial without a jury (maybe a stretch, but I think it’s a stimulating thought).
Continue reading Juries: The Original Fairness Calculator

Giving Helpful Feedback To Awesome Developers

How do you give useful feedback to a coworker who is solving a technical problem outside of your area of expertise? This issue surfaces in all kinds of highly skilled work, from design to engineering to finance to basic science. It’s also highly relevant for technical and non-technical founders of a software start-up. Continue reading Giving Helpful Feedback To Awesome Developers

Retiring At 30 Through Splitting Costs

An interesting writer named Mr Money Mustache wrote this week on MSN money explaining how he was able to retire at age 30 with all the money he saved on rent by sharing with his friends and future wife.

While he had a rather above-average salary in a location with relatively cheap housing expenses, I was impressed by his vision of home-sharing as a path to financial and career freedom. Though personally, I don’t think my fiancee and I could keep my spending that low with those incomes, sharing a bedroom or not! You can read the inglorious details of his year-by-year savings in the original article.