<?xml version="1.0" encoding="US-ASCII" ?>
    <!-- Field: Doc-Info; Name: Generator; Value: GoFiler Complete; Version: 6.5b -->
    <!-- Field: Doc-Info; Name: VendorURI; Value: https://www.novaworks.com -->
    <!-- Field: Doc-Info; Name: Status; Value: 0x00000000 -->
    <!-- Field: Doc-Info; Name: Misc; Value: +6spw7xRiXhun8uCbn1MSaeEabP9w5dzqelBtm9yHSkKPy4id7iLeCLt470m4Z8H -->
<schema xmlns="http://www.w3.org/2001/XMLSchema" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrldi="http://xbrl.org/2006/xbrldi" xmlns:dei="http://xbrl.sec.gov/dei/2025" xmlns:us-gaap="http://fasb.org/us-gaap/2025" xmlns:oef="http://xbrl.sec.gov/oef/2025" xmlns:dtr-types="http://www.xbrl.org/dtr/type/2024-01-31" xmlns:navfx="http://fundinfopages.com/20260331" elementFormDefault="qualified" targetNamespace="http://fundinfopages.com/20260331">
    <annotation>
      <appinfo>
        <link:linkbaseRef xlink:type="simple" xlink:href="navfx-20260331_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Presentation Links" />
        <link:linkbaseRef xlink:type="simple" xlink:href="navfx-20260331_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Label Links" />
        <link:linkbaseRef xlink:type="simple" xlink:href="navfx-20260331_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Definition Links" />
      </appinfo>
    </annotation>
    <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
    <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
    <import namespace="http://xbrl.sec.gov/dei/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-2025.xsd" />
    <import namespace="http://fasb.org/us-gaap/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd" />
    <import namespace="http://fasb.org/us-types/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-types-2025.xsd" />
    <import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
    <import namespace="http://xbrl.sec.gov/oef/2025" schemaLocation="https://xbrl.sec.gov/oef/2025/oef-2025.xsd" />
    <import namespace="http://xbrl.sec.gov/oef-sr/2025" schemaLocation="https://xbrl.sec.gov/oef/2025/oef-sr-2025.xsd" />
    <import namespace="http://xbrl.sec.gov/country/2025" schemaLocation="https://xbrl.sec.gov/country/2025/country-2025.xsd" />
    <import namespace="http://fasb.org/srt/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd" />
    <import namespace="http://fasb.org/srt-types/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-types-2025.xsd" />
    <element id="navfx_C000100305Member" name="C000100305Member" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_CommoditiesSectorMember" name="CommoditiesSectorMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_ShortTermInvestmentSectorMember" name="ShortTermInvestmentSectorMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_VanguardCommunicationServicesETFMember" name="VanguardCommunicationServicesETFMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_VanguardIndustrialsETFMember" name="VanguardIndustrialsETFMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_VanguardInformationTechnologyETFMember" name="VanguardInformationTechnologyETFMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_VanguardConsumerDiscretionaryETFMember" name="VanguardConsumerDiscretionaryETFMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_VanguardHealthCareETFMember" name="VanguardHealthCareETFMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_FidelityTreasuryPortfolioMember" name="FidelityTreasuryPortfolioMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_ProSharesUltraSilverMember" name="ProSharesUltraSilverMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_VanguardLargeCapETFMember" name="VanguardLargeCapETFMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_ProSharesUltraShortBloombergCrudeOilMember" name="ProSharesUltraShortBloombergCrudeOilMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="navfx_StateStreetSPDRSandP500ETFTrustMember" name="StateStreetSPDRSandP500ETFTrustMember" abstract="true" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
</schema>
